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Hemorrhage in mice results in decreased ATP levels in the jejunum, lung, kidney, heart, and brain but not in liver tissue lysates, albeit at variable levels and time kinetics. The decreased protein expression and activity of pyruvate dehydrogenase (PDH) accounted for the hemorrhage-induced ATP loss. Treatment with geldanamycin (GA: 1 [micro]g/g body wt), a known inducer of heat shock protein (HSP)70, inhibited the hemorrhage-induced ATP loss in the jejunum, lung, heart, kidney, and brain. GA was found to increase PDH protein, preserve PDH enzymatic activity, and inhibit mucosal injury in jejunum tissues. GA-induced HSP70i was found to form complexes with PDH protein. HSP70 gene transfer into intestinal epithelial cells promoted PDH and ATP levels, whereas HSP70 short interfering RNA limited them. We conclude that agents able to increase the expression of HSP70 and PDH may be of value in reducing pathology resulting from hemorrhage-associated ATP loss. heat shock protein 70; intestine

The nitric oxide (NO) synthase inhibitor [N.sup.[omega]]-nitro-L-arginine (L-NNA) inhibits heat stress (HS)-induced NO production and the inducible 70-kDa heat shock protein (HSP-70i) in many rodent organs. We used human intestinal epithelial T84 cells to characterize the inhibitory effect of L-NNA on HS-induced HSP-70i expression. Intracellular [Ca.sup.2+] concentration ([[[Ca.sup.2+]].sub.i]) was measured using fura-2, and protein kinase C (PKC), and PKA activities were determined. HS increased HSP-70i mRNA and protein in T84 cells exposed to 45 [degrees] C for 10 min and allowed to recover for 6 h. L-NNA treatment for 1 h before HS inhibited the induction of HSP-70i mRNA and protein, with an I[C.sub.50] of 0.0471 [+ or -] 0.0007 [micro]M. Because the HS-induced increase in HSP-70i mRNA and protein is [Ca.sup.2+] dependent, we measured [[[Ca.sup.2+]].sub.i] after treating cells with L-NNA. L-NNA at 100 [micro]M significantly decreased resting [[[Ca.sup.2+]].sub.i]. Likewise, treatment with 1 [micro]M GF-109203X or H-89 (inhibitors of PKC and PKA, respectively) for 30 min also significantly decreased [[[Ca.sup.2+]].sub.i] and inhibited HS-induced increase in HSP-70i. GF-109203X- or H-89-treated cells failed to respond to L-NNA by further decreasing [[[Ca.sup.2+]].sub.i] and HSP-70i. L-NNA effectively blocked heat shock factor-1 (HSF1) translocation from the cytosol to the nucleus, a process requiring PKC phosphorylation. These results suggest that L-NNA inhibits HSP-70i by reducing [[[Ca.sup.2+]].sub.i] and decreasing PKC and PKA activity, thereby blocking HSF1 translocation from the cytosol to the nucleus. heat; nitric oxide; heat shock protein; protein kinase C; protein kinase A

Rise in intracellular Ca2+ concentration and stimulation of G proteins enhance the synthesis of highly-conserved 70-kDa heat-shock proteins (HSP-70). The increase and stimulation depend on the time of heating and the temperature. HSP-70 synthesis is independent of intracellular pH and adenosine 3',5', -cyclic monophosphate.

An investigation on the effect of heat shock, extracellular calcium ion concentration and cAMP on the inositol triphosphate in the human epidemic cells shows that the increase in intracellular Ca iron concentration and the activation of G proteins causes the heat induced increase in InsP3. The use in intracellular Calcium is increased by the adonosine 3',5'-cyclic monophosphate-induced increase. The heat induced intracellular acidification has no effect on the increase in InSp3.

The aim of this study was to determine whether hemorrhage altered the caspase-3 activity and the ATP levels in rat lung and ileum tissues and determine whether resuscitation with lactated Ringer solution (LR) or whole blood (WB reversed these changes. Male Sprague­Dawley rats were briefly anesthetized with isoflurane, and their mean arterial blood pressure was reduced from 110 to 40 mmHg by bleeding. The bled rat was then resuscitated with LR or autologous WB to bring mean arterial blood pressure back to 80 mmHg. Lung and ileum tissues were removed at the end of hemorrhage or at the end of the resuscitation period for specified bioassays. Hemorrhage increased cellular caspase-3 activity in the lung and the ileum. After the hemorrhaged rats received LR or WB, caspase-3 activity returned to the basal level in the lung and ileum, respectively. Likewise, hemorrhage decreased cellular ATP levels in lung and ileum. After LR or WB resuscitation, the cellular ATP level returned to the basal level only in the lung resuscitated with LR. The increased caspase-3 activity was associated with the increased expression of caspase-3 mRNA, which also returned to normal levels after either resuscitation. Similarly, hemorrhage increased the expression of inducible nitric oxide synthase and Kruppel-like factor 6 and decreased expression of Kruppel-like factor 4. Subsequent LR resuscitation normalized the expression of these genes in the lung tissue. Our results demonstrate that resuscitation with LR can reverse the expression of genes and their products that are thought to contribute to hemorrhage-induced lung injury. [ABSTRACT FROM AUTHOR]

Characterizes the inhibitory effect of n[sup omega]-nitro-L-arginine (L-NNA) on heat stress-induced heat shock protein-70i (HSP-70i) expression. Evidence showing that the L-NNA inhibits heat stress-induced increases in HSP-70i; Evidence showing that L-NNA inhibits increase in HSP-701 at mRNA level.