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The undescended testis is associated with an increased incidence of testicular malignancy. The position of the undescended testis is related to the likelihood of carcinogenesis, with the intra-abdominal testis having the highest malignant potential. We present 3 patients to illustrate this tendency and to highlight the unusual presentation as an "acute abdomen".

1. Primary monolayer cultures from adult human epididymis were grown on Petri dishes and previous supports. The epithelia so formed were used for whole-cell patch clamp recording and short-circuit current (ISC) measurement. 2. After 50 days of culture, the cells formed a tight epithelium with transepithelial potential of 5.5 +/- 1.3 mV (mean +/- S.E.M.., n = 16), apical side negative, and a basal ISC of 6.9 +/- 0.9 microA cm-2 (mean +/- S.E.M., n = 16). 3. Adrenaline, when added to the basolateral side, at a concentration of 0.23 mumol l-1 increased the ISC by 3.0 +/- 1.2 microA cm-2 (mean +/- S.E.M., n = 4). This increase was blockable by diphenylamine-2-carboxylate (DPC, 1 mmol l-1). Forskolin (10 mumol l-1) also evoked a similar response to adrenaline. 4. In whole-cell patch clamp experiment, the resting membrane potential of the cells after dialysis with pipette solution containing 135 mmol l-1 KCl was found to be -30 +/- 14 mV (mean +/- S.E.M., n = 15). 5. About 90% of the cells successfully forming patches responded to 1 mumol l-1 adrenaline by an increase in inward current at -70 mV holding potential (delta I = -1600 +/- 900 pA, mean +/- S.E.M., n = 15). This increase in current was accompanied by a shift in reversal potential to -2 +/- 1 mV (mean +/- S.E.M., n = 15). 6. The adrenaline-induced inward current was found to be blockable by the Cl- channel blocker, DPC (0.25 mmol l-1). Ion substitution experiments showed that the adrenaline-evoked current was carried mainly by Cl-. 7. The effect of adrenaline on the whole-cell current was found to be mimicked by forskolin and could be abolished by including GDP beta S or a protein kinase A inhibitor in the pipette solution. Propranolol, but not phentolamine, completely abolished the effect of adrenaline. 8. Inclusion of 20 mmol l-1 EGTA or 2 mmol l-1 BAPTA + 100 mumol l-1 TMB-8 (to inhibit intracellular Ca2+ release) in the pipette did not seem to have any marked effect on adrenaline-evoked whole-cell current. Lowering the pipette Ca2+ concentration to 1 nmol l-1 or raising it to 10 mumol l-1 had no effect on the whole-cell current response to adrenaline. 9. This study shows that adrenaline stimulates Cl- secretion in cultured human epididymal cells.(ABSTRACT TRUNCATED AT 400 WORDS)

Sloughed necrotic papillae usually show soft tissue sonographic characteristics. We report a patient who presented with septicaemia and pyonephrosis due to ureteric obstruction caused by shed necrotic papillae. These were echogenic on ultrasound, and resembled calculi.

Joint laxity was measured clinically in 2,360 normal Chinese children aged 3-13 years with equal sex distribution using the Carter Wilkinson five tests and scoring system. Results showed minimal differences due to gender. The degree of joint laxity diminished with age. The knee extension and ankle extension tests were more sensitive than other tests. Chinese children were far more lax throughout the age range, with 100% "laxity" at age 3, 67% laxity at age 6, and 28% laxity at age 12, in contrast to 50, 5, and 1% laxity in the same age group respectively, in large series of Caucasian children.

Angular and rotational profile of the lower limbs of 2,630 normal Chinese children from newborn to age 12 years were compiled using tibiofemoral angle, intercondylar, intermalleolar distance, medial and lateral rotation of the hip, and thigh-foot angle. Children with clinical tibiofemoral angles, intercondylar or intermalleolar distances tended to be bowlegged at birth, maximally knock-kneed at age 3 and to have normal lower limbs by age 8. Medial hip rotation increased steadily from birth to a maximum of 56 degrees at age 9, and lateral hip rotation decreased from birth to a minimum of 30 degrees at age 9. Significant differences between Chinese children and children of other races were highlighted.

A case of emphysematous pyelonephritis is reported. The initially puzzling plain abdominal radiographs simulated intestinal obstruction and pneumatosis intestinalis. Resolution was later confirmed sonographically.

Under strict indications, ureterorenoscopic (URS) lithotripsy was used to treat ureteric calculi in 61 patients under local anaesthesia and sedation in a 2-year period ending November 1988. Assessments of success and discomfort of the procedure were made. Stone retrieval was accomplished in 48 patients (78% success rate) and a mean pain score of 6 was recorded in a scale from 0 to 10. It was concluded that performing URS under local anaesthesia is an acceptable alternative.

The title compounds were prepared as the heterocyclic analogues of thromboxane (TX) synthetase inhibitors and antihypertensive agents previously reported from our laboratories. These compounds were at least as active TX synthetase inhibitors as their benzene isosteres with the indole derivatives 50-55 having the most potent enzyme inhibiting activity measured to date in our laboratories. The best compound, 54, is more than 200-fold more potent than the standard, dazoxiben. In contrast, the antihypertensive activity of these series of compounds was no better than their benzene counterparts and is far lower than the isoindoledione derivatives prepared in a related series. The structure-activity relationship results from this study were similar to our previous observations and include the fact that the amide moiety effectively replaces a carboxylic acid for potent TX synthetase inhibition and that a four to six methylene unit separation (approximately 8.5 A) between amide and imidazole moieties achieves maximal activity.

Selective inhibitors of thromboxane (TX) formation have potential utility in the treatment of hypertension, atherosclerosis, thrombosis, myocardial ischemia, cancer metastasis, etc. This class of compounds not only removes TX, a potent vasoconstrictor and inducer of platelet aggregation, but may also enhance the production of a potent vasodilator and inhibitor of platelet aggregation, viz., prostacyclin (epoprostenol, PGI2). The specific thromboxane synthetase (TXS) inhibitor 1-benzylimidazole (1-BI) demonstrated a weak and OKY-1581 (OKY) a potent inhibition of TX formation in SHR-derived platelets in vitro. The acute antihypertensive effects produced by 1-BI were marked while those of OKY were less significant in SHR. 1-BI and OKY did not demonstrate an inhibition of PGI2 formation in SHR-derived aortic rings in vitro. Indomethacin (I), which inhibits the formation of both TX and PGI2, was not antihypertensive and did not antagonize the blood pressure lowering effects of 1-BI in the present studies. Oral and intravenous dosing with 1-BI, unlike OKY, produced epinephrine reversal in SHR, indicating the blockade of alpha-adrenoceptors. In conclusion, the acute antihypertensive effects of 1-BI in SHR result mainly from alpha-adrenoceptor blockade, not inhibition of TXS activity.

Angiomyolipomas produce pathognomonic appearances on modern imaging methods and a tissue diagnosis is no longer required particularly when multiple tubers can be confidently diagnosed and if a CT brain scan shows periventricular calcifications. As the renal tumours are benign every effort must be made to preserve normal renal tissue. Symptomatic or large tumours can be effectively treated by transcatheter embolisation with a reduction in the size of the tumour and control of intratumoural haemorrhage.

Viprostol [(dl)-15-deoxy-16-hydroxy-16(alpha/beta)-vinyl-prostaglandin E2 methyl ester; CL 115 347] is a new orally and transdermally active antihypertensive agent that exerts its major antihypertensive action by vasodilation. The present studies were conducted to examine its effects on the adrenergic nervous system. In cats, viprostol did not inhibit renal sympathetic nerve discharge (RSND) monitored at the postganglionic region, indicating that nerve transmission or conduction was not blocked at the ganglion or the pre- or postganglionic fibres. In cat nictitating membrane preparations in situ, viprostol partially blocked the membrane contractile response to exogenous epinephrine and norepinephrine, as well as to electrical stimulation of pre- and postganglionic fibres. In spontaneously hypertensive rats (SHR), viprostol partially blocked the vasopressor response of exogenous norepinephrine and epinephrine specifically without influencing that of angiotensin II. All these suggest that viprostol produced weak alpha-adrenoceptor blockade. Viprostol did not antagonize the tachycardia induced by stimulation of the discrete segments at C7-T1 (cardio-accelerator) of the spinal cord in pithed SHR, suggesting that viprostol did not activate the presynaptic alpha-adrenoceptors. Viprostol significantly inhibited the increase in blood pressure induced by electrical stimulation of the spinal cord at T7-T9 in pithed SHR, probably due to postsynaptic alpha-adrenoceptor blockade. In conclusion, viprostol produced weak, but statistically significant alpha-adrenoceptor blockade which may contribute partially to its antihypertensive action.

Viprostol [(dl)-15-deoxy-16-hydroxy-16(alpha/beta)-vinyl-prostaglandin E2 methyl ester; CL 115 347], injected directly into coronary, renal, mesenteric, femoral and carotid arteries of the anaesthetized beagle dogs at doses which did not lower the systemic arterial blood pressure, increased blood flow of the vascular beds being studied. Viprostol was as potent as I-prostaglandin E2 (I-PGE2) in the renal bed, but less potent in the other vascular beds. Viprostol was as potent as I-PGE2 in relaxing smooth muscle of the perfused isolated central ear artery of the rabbit. Viprostol maintained its antihypertensive effect in spontaneously hypertensive rats (SHR) pretreated with indomethacin, chlorpheniramine plus cimetidine, atropine or propranolol, suggesting that the vasodilating effects of viprostol were not mediated through the endogenous prostaglandin, histamine, cholinergic nervous system or beta-adrenergic nervous system. The antihypertensive effects of viprostol were not altered in SHR with bilateral nephrectomy or bilaterally ligated ureters, suggesting that the action of viprostol was not dependent on the secretory or excretory functions of the kidneys. In conclusion, viprostol exerts its antihypertensive action mainly by vasodilation in a way similar to the natural PGE2.

In spontaneously hypertensive rats (SHR), captopril at 30 and hydrochlorothiazide (HCTZ) at 100 mg/kg/day p.o. for 2 days lowered mean arterial blood pressure (MABP) 16 and 10 mm Hg, respectively. Treatment with the combination of captopril plus HCTZ for one day lowered MABP to the same extent as captopril alone, but produced a synergistic 44 mm Hg MABP lowering after the second day combination treatment. Bilateral ureteral ligation did not prevent the synergistic antihypertensive effect demonstrating that removal of electrolytes was not the cause of this effect. Cardiovascular responses to angiotensin-I and -II, norepinephrine or bradykinin did not differ in rats given the combination or captopril alone. After the combination treatment for one day, captopril but not HCTZ alone on the second day lowered MABP in rats to the same degree as in those receiving the combination treatment for 2 days, suggesting that the diuretic action per se is unimportant. Captopril and HCTZ increased plasma renin activity (PRA) but only the combination of captopril and HCTZ produced a greater and longer lasting increase of PRA. It is concluded that the mechanism for the synergism is the renin dependency, created by the combination of HCTZ and captopril, resulting in a greater role of the renin system in blood pressure control and increased responsiveness to angiotensin converting enzyme inhibition by captopril.

Topically applied 16-vinylprostaglandins demonstrate the property of rapid transit through the skin and a profound effect on the cutaneous vasculature. At low concentrations in the guinea pig and rabbit. 15-deoxy-16-hydroxy-16-vinyl-PGE2 (DHV-PGE2) and its methyl ester (DHV-PGE2Me) elicit a distinct and persistent erythema which is restricted to the area of application and is not associated with a wheal. Skin temperatures are elevated for several hours following application. Accordingly, these compounds may have therapeutic utility in conditions where local blood flow is compromised or where an enhanced blood flow is desired . In the spontaneously hypertensive rat, topically applied DHV-PGE2 and DHV-PGE2Me produce a dramatic and persistent lowering of blood pressure. The maximal effects are comparable to those obtained wit equal oral or intravenous doses and are maintained for a longer period of time. Moreover, with the topical route, there is no prolongation in the time required for onset of action (3-5 minutes). It appears that while the skin presents only a minimal diffusion barrier to these compounds, a sufficient depot is maintained to give sustained release and prolonged duration. Transdermal delivery of 16-vinyl prostaglandins may offer a convenient means of achieving a clinical antihypertensive effect without the characteristic side effects generally associated with oral or intravascular prostaglandins.

A series of 5-(1-piperazinyl)-1H-1,2,4-triazol-3-amines was synthesized and screened for antihypertensive and diuretic activity in spontaneously hypertensive rats (SHR). One compound, 5-[4-[(3-chlorophenyl)methyl]-1-piperazinyl]-1H-1,2,4-triazol-3-am ine (8), was selected to define the mechanism of its antihypertensive activity. Studies in SHR suggest ganglionic blocking activity. Short-lived antihypertensive activity was observed in conscious renal hypertensive dogs.

The occurrence of early life threatening arrhythmias in the ischemic myocardium has been associated with local generation of thromboxane (TX). Antiarrhythmic agents are typically classified according to the fundamental mechanism involved in restoring normal rhythm but identifying those agents also capable of suppressing TX formation offers a means of improving the rationale of antiarrhythmic therapy. Accordingly, representative antiarrhythmic agents from classes I-IV were evaluated in the present study for their ability to suppress TX formation from intact rat platelets, in vitro. Agents from class I, II and IV achieved significant reductions in TX levels as compared to a reference TX inhibitor, dazoxiben. The IC-50 value for dazoxiben was 1.5 X 10(-6) M. Nicardipine and flecainide, being the most active of the antiarrhythmic agents tested, had IC-50's of 5 X 10(-6) and 1 X 10(-5) M respectively. Verapamil and propranolol had values of 1 X 10(-5) and 5 X 10(-5) M respectively; labetalol and quinidine were 5 X 10(-5) M, and phenytoin and diltiazem were approximately 1 X 10(-4) M. These data suggest a subsidiary antiarrhythmic property of these particular agents as related to their ability to suppress TX generation in the ischemic myocardium and implies these agents may be preferred in the treatment of early life threatening arrhythmias resulting as an initial response to myocardial ischemia.

The title compounds were prepared to investigate their potential as thromboxane synthetase inhibitors as well as antihypertensive agents. Imidazoles VIII and triazoles X were prepared to examine the effects of aromatic substitution, chain length, and heterocycle substitution upon biological activity. Imidazoles VIII and triazoles X were thromboxane synthetase inhibitors that did not inhibit prostacyclin formation. The most interesting thromboxane synthetase inhibitors prepared were 4-chloro-, 4-(trifluoromethyl)-, and 4-bromobenzamide derivatives of (1H-imidazol-1-yl)alkylamines with C5-C8 alkyl chains separating the heterocycle from the amide moiety, while the most active antihypertensive agents were 3- or 4-chloro-, -bromo, or -(trifluoromethyl)benzamides with C3 alkyl chains. The best thromboxane synthetase inhibitors in this study were up to 10 times more potent than the standard, dazoxiben (UK 37,248).

Eleven quinazolinylformamidines and quinazolinediylbisformamidines were synthesized and investigated for antihypertensive activity in spontaneous hypertensive rats. Several compounds showed moderate antihypertensive activity at 100 mg/kg po. The same compounds were not hypotensive in the normotensive dog.

In spontaneously hypertensive rats (SHR), after 1 day of dosing with an angiotensin-converting enzyme (ACE) inhibitor (captopril or enalapril) plus a diuretic (hydrochlorothiazide), a synergistic antihypertensive effect was observed when a second dose of the combination or ACE inhibitor alone but not the diuretic alone was given the next day. Bilateral ureteral ligation did not prevent the synergism, which indicates that diuresis per se was not the mechanism. Vascular responses to various agonists did not differ in SHR given ACE inhibitor or ACE inhibitor plus diuretic. SHR given combination treatment had higher and more prolonged increases in plasma renin activity. Aprotinin or indomethacin did not alter the synergism, which suggests that endogenous kinins and prostaglandins did not play a role. These data suggest that the mechanism for the synergistic antihypertensive effect resulted from the combination treatment's shifting the blood pressure regulation system to be renin dependent and responding more to drugs affecting the renin-angiotensin system (RAS). Evidence was presented that the RAS can be shifted rapidly to assume a greater role in blood pressure regulation in SHR as well as in normotensive and two-kidney, one-clip Goldblatt renal hypertensive dogs by restricting sodium intake. The data may partly explain the various degrees of antihypertensive responsiveness of essential hypertensive patients to ACE inhibitors.

Melioidosis is endemic in Southeast Asia but reports of prostatic involvement are rare. We describe a patient with Pseudomonas pseudomallei septicemia and a prostatic abscess who presented with signs and symptoms of a urinary tract infection. The organism was cultured from the blood, urine and prostatic pus, and was treated successfully with co-trimoxazole and surgical drainage. Genitourinary infection with Pseudomonas pseudomallei should be considered in patients from endemic areas, and bacteriological investigation is essential for the diagnosis and management.

A combined method for detecting compounds with antihypertensive and diuretic activity simultaneously in the same spontaneously hypertensive (SH) rat is described. The present method, utilizing the advantages of sequential probability test analysis, the spontaneously hypertensive rats and the direct measurement of arterial blood pressure, proves to be feasible and efficient in detecting both activities. This ia s 3-stage sequential test requires one to three rats per compound. One adult SH rat was dosed by gavage with compound at 100 mg/kg, p.o. and loaded with 0.9% NaCl at 25 ml/kg, p.o. at 0-hr. The rat was put in a metabolism cage. The 0-5 hr. urine was collected and urinary Na+, K+ and CL- were determined. A second identical dose was given without NaCl loading at 24-hr. Mean arterial blood pressure (MABP) of conscious rats was measured directly by fermoral-iliac artery puncture at 28-hr. The criteria to accept, retest or reject a compound were based on the testing of known antihypertensives and diuretics. A 2nd and 3rd rat may be needed for a test compound depending on the outcome of the MABP and urinary electrolytes of the 1st rat. Based on MABP, guancydine, hydralazine, clonidine, reserpine, alpha-methyldopa, guanethidine and parglyine were accepted as active. Based on urinary sodium excretion, furosemide, quinethazone, acetazolamide, hydrochlorothiazide, metolazone, triamterene and clonidine were accepted as active.

Two patients with primary peritoneal mesothelioma are reported. They had abdominal symptoms, no symptoms referable to the respiratory system and normal chest X-rays. There was no clinical evidence of impaired respiratory function. One of the patients had a history of brief asbestos exposure over 20 years before diagnosis. The procedure for obtaining compensation is outlined and the protean uses of, and hence possible exposure to, asbestos are noted. In screening programmes consideration should be given to both pulmonary and abdominal symptoms. Laparoscopy may have a part to play in earlier diagnosis of peritoneal mesothelioma.

The quinazolinedione, quinazolinone, and 1,2,3-benzotriazinone title compounds were prepared as analogues of N-[(1H-imidazol-1-yl)alkyl]-1H-isoindole-1,3(2H)-diones which were the subject of a previous report from our laboratories. These compounds were evaluated as thromboxane (TX) synthetase inhibitors and as antihypertensive agents. While each series of compounds had activity both as TX synthetase inhibitors and as antihypertensives, the best compounds were N-[(1H-imidazol-1-yl)alkyl]quinazoline-2,4(1H,3H]-diones (V). In general these compounds were all selective enzyme inhibitors at least equipotent with the standard dazoxiben. These compounds were also very active antihypertensive agents as determined in SHR. The SAR is discussed for both types of activity. Compound 20a was further evaluated for TX formation inhibiting properties in several other platelet types both in vitro and ex vivo and is between 100 and 1000 times more potent than dazoxiben.

CL 115,347 orally (0.25-10 mg/kg) and topically (0.03 and 0.1 mg/kg) lowered blood pressure in a dose-dependent manner in conscious spontaneously hypertensive rats (SHR). Duration of action of the oral dose range was from 1 to more than 8 h and of the topical dose range, from more than 6 to more than 24 h. CL 115,347 was 100-200 times more potent orally and greater than 250 times more potent topically than l-prostaglandin (PG) E2. When 3 mg/kg was administered orally, CL 115,347 was also active in Dahl "S" salt-sensitive hypertensive rats, deoxycorticosterone acetate-salt hypertensive rats, aorta-coarcted renin-dependent hypertensive rats, normotensive rats, bilaterally nephrectomized SHR, and bilaterally ureteral-ligated SHR. CL 115,347 was also orally active at 0.1 mg/kg in normotensive rhesus monkeys and in renal hypertensive dogs at 1 mg/kg. CL 115,347 was as active as l-PGE2 in relaxing the rabbit ear arterial smooth muscle in vitro. In anesthetized dogs, CL 115,347 injected intra-arterially (0.5-10 micrograms) into the vascular bed being studied increased blood flow to femoral, carotid, coronary, superior mesenteric, and renal vascular beds. CL 115,347 decreased vasopressor responses induced by electrical stimulation of the spinal cord at T7-T9 but did not decrease the tachycardia induced by stimulation of the cardioaccelerator segments (C7-T1) in pithed SHR. CL 115,347 has a broad spectrum of antihypertensive activity in various animal models and probably exerts its major antihypertensive effects through relaxation of blood vessels.

CL 115,347 [dl-15-deoxy-16-hydroxy-16(alpha/beta)-vinyl prostaglandin E2 methyl ester] has a broad spectrum of antihypertensive activity in many animal hypertension models in every species tested. In conscious spontaneously hypertensive rats, CL 115,347 at 0.25 to 10 mg/kg orally produced 31 to 53 mm Hg lowering of the mean arterial blood pressure (MABP) with a duration of action of 1 to greater than 8 hr. When applied transdermally, CL 115,347 was more potent and longer acting than by the oral route. At 0.03 to 1 mg/kg, topically applied CL 115,347 lowered MABP of spontaneously hypertensive rats 27 to 46 mm Hg. Duration of action was greater than 6 to greater than 24 hr. CL 115,347 was also active in conscious normotensive rats (-27 mm Hg), deoxycorticosterone-salt-induced hypertensive rats (-51 mm Hg) and aorta-coarcted hypertensive rats (-52 mm Hg) when tested at 1 mg/kg orally. At 3 mg/kg orally, CL 115,347 lowered MABP of Dahl "S" salt-sensitive rats 55 mm Hg. CL 115,347 orally and s.c. lowered MABP in two-kidney, one-clip Goldblatt renal hypertensive dogs and was accompanied by tachycardia. CL 115,347, at 0.1 and 0.2 mg/kg orally, maximally lowered the systolic blood pressure of conscious rhesus monkeys 33 to 63 mm Hg with only a slight increase in heart rate. Therefore, CL 115,347 was antihypertensive in animals with low, normal and high plasma renin activity. The present findings suggest that CL 115,347 may be useful for the treatment of human hypertension.

Contractile responses to norepinephrine, serotonin and potassium (K+) and relaxant responses to isoproterenol and papaverine were studied in vitro with spirally cut thoracic aortic strips from aortic coarcted hypertensive rats (AHR)2, 6, 14 and 28 days postoperatively and compared to time-matched, sham-operated normotensive controls. At every stage after coarctation, the rats developed hypertension with elevated plasma renin activity. In response to stimulation by norepinephrine and serotonin, aortic strips from 2 to 28 day AHR developed the same tension as controls, whereas aortas of 6 and 14 day AHR had reduced maximal responses. For K+-stimulated aortic strips, maximal contractile force was decreased at 6 day AHR only. Relaxation by isoproterenol and papaverine in serotonin-contracted aortas was the same in AHR and normotensive controls 2 and 28 days postoperatively but was reduced at 6 and 14 days. The demonstrated changes of vascular contractility and relaxation in AHR is a hypertensive stage-dependent phenomenon. It is speculated that 6 and 14 days after coarctation the diminished relaxant ability of the aortas helps to maintain the elevated blood pressure and the diminished sensitivity to contractile stimulants is a protective mechanism in response to the elevated blood pressure. The return of normal contraction and relaxation to the agonists in the chronic stage of hypertension may possibly reflect an adaptive change to the prolonged stimulus of the elevated blood pressure that aortic tissue had undergone in order to maintain normal physiologic functions.

CL 115,129, the corresponding carboxylic acid and major metabolite of CL 115,347 (d,1-15-deoxy-16-hydroxy-16(alpha/beta)-vinyl-prostaglandin E2 methyl ester), a potent orally and transdermally long acting antihypertensive agent, infused at 0.1 microgram/kg/min into the left renal artery of sodium pentobarbital anesthetized beagle dogs increased urinary volume, sodium (Na+), potassium (K+) and chloride (Cl-) excretion of the left kidney 289, 201, 101 and 229%, respectively, over the 30 min vehicle-treated control periods. At 0.3 microgram/kg/min CL 115,129 caused a 475 and 336% increase in urinary volume and Na+, respectively. l-Prostaglandin E2 (l-PGE2) infused at 0.1 microgram/kg/min into the left renal artery increased urinary volume, Na+, K+ and Cl- excretion of the left kidney of anesthetized beagle dogs 416, 234, 112 and 255%, respectively, over the control. Both CL 115,129 and l-PGE2 did not affect the systemic arterial blood pressure or the electrolyte excretion of the contralateral kidney. It is concluded that in contrast to other conventional vasodilators, which may cause severe water and electrolyte retention, CL 115,347, via its metabolite CL 115,129, may cause diuresis and natriuresis in many clinical settings when used as an antihypertensive.

The effects of three formulations on the transdermal absorption and antihypertensive activity of 14C-viprostol were investigated in the spontaneously hypertensive rat. Single doses of 14C-viprostol were administered topically to rats in three formulations: silicone oil, petrolatum base, and triethyl citrate (TEC). Mean arterial blood pressure (MABP) and blood concentrations of radioactivity were measured over 24 h. Metabolic profiles in the skin were determined by HPLC; in vitro skin metabolism was also investigated. Following topical dosing with 14C-viprostol in petrolatum and silicone oil, substantial systemic concentrations of radioactivity and decreases in MABP were observed. In contrast, administration of 14C-viprostol in TEC led to negligible blood concentrations of radioactivity and the lowering of MABP was diminished. Metabolic profiles in skin at the application site from rats dosed with viprostol in petrolatum and silicone oil indicated rapid hydrolysis of the viprostol methyl ester to the active free acid, CL 115,129. When TEC was used as the dosing vehicle, the conversion of viprostol to the free acid appeared to be slower. TEC (an ester itself) was also found to reduce the rate of hydrolysis of viprostol in rat skin 10,000-g supernatants.

1 Quantitative studies were made on the glucose release from rabbit liver slices in vitro induced by a range of concentrations of (-)-adrenaline (Ad), (-)-isoprenaline (Iso), glucagon and adenosine 3',5'-monophosphate (cyclic AMP) in the presence and absence of several concentrations of dihydroergotamine (DHE). 2 DHE (3.16 X 10(-6) M) shifted the Ad log concentration-response (LCR) curve to the right and also reduced the maximum response; at a higher concentration (3.16 x 10(-5) M) it produced a greater shift to the right of the LCR curve and caused a reduction in the slope and a larger depression of the maximal responses. The LCR curve to Iso was similarly affected by this higher concentration of DHE. 3 DHE (1 X 10(-5) M) produced no significant effect on the LCR curves of glucagon or cyclic AMP and even at 1 x 10(-4) M DHE caused only a slight depression of the maximal responses to both agonists without any modification of the lower major portions of the curves. 4 These data indicate a selective antagonism by DHE at the rabbit liver adrenoceptor and, since the maximal responses to catecholamines were depressed by a lower concentration of DHE than was required to produce a slight depression of the responses to glucagon and cyclic AMP, the antagonism of DHE against catecholamines does not appear to be at a site beyond the formation of cyclic AMP, but rather at a site more intimately related to the adrenoceptor.

Captopril (30 mg/kg/day orally for two days) in spontaneously hypertensive rats (SHR) inhibited serum angiotensin converting enzyme (ACE) activity 92.3%; increased plasma renin activity (PRA) 18-fold and reduced mean arterial blood pressure (MABP) 19 mm Hg. Hydrochlorothiazide (HCTZ) (100 mg/kg-day 1; 10 mg/kg-day 2, orally) increased PRA 3-fold but did not affect serum ACE or MABP. HCTZ plus captopril inhibited serum ACE 95.2%; increased PRA 38-fold and reduced MABP 47.5 mm Hg. Captopril or HCTZ plus captopril did not alter the responses of isolated aortic strips to norepinephrine (NE), serotonin, angiotensin II (AII) or isoproterenol. Pressor responses of conscious SHR to AII and NE were unaltered by captopril or HCTZ plus captopril although the bradykinin-induced depressor responses were significantly but equally potentiated. These results suggest that the potentiating effect of HCTZ is due to some mechanism that shifts the animal's blood pressure maintenance system to a renin-dependent state and is not due to changes in vascular reactivity.

The synthesis of a series of N2-[4-[(arylmethyl)amino]-2, 6-dichlorophenyl]-N1,N1-dimethylformamidines that caused marked blood pressure lowering and/or diuresis in spontaneously hypertensive rats (SHR) is reported. Diuretic activity was not always associated with acute antihypertensive activity. Central nervous system effects, most notably sedation, were observed. Compound 9d, which lowered arterial blood pressure 37 mmHg in SHR when dosed at 100 mg/kg, was further evaluated in chronic hypertensive dogs because of apparent minimal CNS effects. A reduction in arterial blood pressure of 32 mmHg at 1.0 mg/kg during a 6-h postdosing interval was observed. This response was unrelated to alpha- or beta-adrenergic blockade, angiotensin I antagonism, or neuronal or ganglionic blockade. CNS effects were also observed.

A series of N-[(1H-heteroaryl)alkyl]-1H-isoindole-1,3(2H)-diones were prepared as part of a continuing investigation into the biological properties of compounds that were both thromboxane synthetase inhibitors and potential antihypertensive agents. The most active thromboxane synthetase inhibition was found for the title imidazole derivatives wherein a hexyl or octyl chain separated the heterocyclic ends of the molecule (5,6) or with substitution on the isoindole portion of the molecule (18, 19, 21, 22, 25, 26). Compounds with shorter alkyl chain separations had good antihypertensive effects (1-5, 8-10, 19-22, 27-30). Butyl derivative 3 was chosen for further evaluation as a potential antihypertensive agent with thromboxane synthetase inhibitory properties.