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In this study, we investigated methamphetamine (METH)- induced peroxidative DNA damage in various regions of the rat brain. We injected METH to rats following 2 protocols. For the single administration experiment (group I), 50 mg/kg (i.p.) of METH was administered to observe the acute influence of METH. For the repeated administration experiment (group II), 10 mg/kg/day (i.p.) of METH was injected for 5 days. Immunohistochemically, peroxidative damage DNA, 8-hydroxy-2’- deoxyguanosine (8-OH-dG) was observed, and in situ apoptosis was also observed. In group I, immunoreactivity of 8-OH-dG was only enhanced in neurons of the nucleus accumben of METH-treated rats. On in situ apoptosis detection, positive findings were also enhanced in all examined parts compared to those in the control, though there were no significant increases in 8-OH-dG-immunopositive neurons except in the nucleus accumben. In group II, the nucleus accumben also showed enhanced 8-OH-dG immunopositivity compared to that in the control. There was no significant difference in apoptosis between the control and METH groups. Based on our observations, it is considered that METH induces oxidative DNA damage in the brain, especially in the nucleus accumben. However, those DNA damage might be caused differently between acute and chronic administration.

A 63-years-oldman was found dead with the body soaking in water lying face up on a riverbank. Autopsy and diatom examination demonstrated that the cause of death was drowning. He had undergone hypophysectomy 20 years earlier. Autopsy, pathological and endocrinological findings demonstrated secondary and chronic hypothyroidism, hypogonadism, and adrenal in sufficiency. The cadaver had fallen into the river, and received numerous wounds such as abrasions and subcutaneous hemorrhage. Moreover, it was suspected that he had developed hypothermia before death. Cortisol in the blood and 17-OHCSin urine were within the reference range. We suspect that the adrenocortical hormone was secreted into the blood as a result of various stresses due to wounds and hypothermia. However, it was suspected that sufficient hormone might not be secreted due to chronic adrenal insufficiency. This insufficient cortisol causes the decrease in the stress resistance, and might influence his cause of death. Moreover, as hypothyroidism decreases thermogenesis, he might have fallen into hypothermia easily. In addition, because both adrenocortical insufficiency and hypothyroidism caused the hypoglycemia, he might have fallen into the loss of consciousness. Therefore, it was considered that he had died by drowning, in relation to the adrenocortical insufficiency and panhypopituitarism.

Forensic autopsy cases detecting methamphetamine (MA) are usually diagnosed according to its toxicological concentration. It has been reported that the lethal blood concentration of MA is 4.48 μg/ml (3.0μmol/dl). We autopsied two MA-detected cadavers, and immunohistochemical staining was performed on the skeletal muscle with an anti-myoglobin antibody, and on the kidney with an anti-the 70 kDa heat shock protein(HSP70) antibody. One case showed a high rectal temperature (40℃). The toxicological examination revealed 0.75μg/ml of MA in the blood, and 16.8 μg/ml in the urine. Myoglobin was negative and HSP70 was positive in the kidney immunohistochemically. From the toxicological and immunohistochemical findings, it was considered that the subject died of hyperthermia and acidosis caused by muscular hyperactivity. In another case, the autopsy revealed highly congested lungs, with dark-red bloody fluid and foam in the trachea and bronchus. MA (17.0 μg/ml) was detected in the blood. HSP70 was negative and myoglobin was positive immunohistochemically. It was thought that the subject died of acute MA intoxication based on the high MA concentration, although rhabdomyolysis was suspected. It is suggested that myoglobin and HSP70 immunostaining are useful to diagnose MA poisoning.

The completely reduced skeleton was found in a mountain stream. We presumed that the skeleton was a woman from a morphology feature of the skull and the pelvis bone. The level of the suture of the skull indicated that the age was the first half of the 70-yearsold from the 60-years old. As a result of the police investigation, the possibility of 66 years old woman who was missing for about six months was suspected. To inquire into her identification, a skull and left thighbone were cut off, and blood was collected from the suspect’s daughters. We examined blood (ABO) and DNA types (D1S80,HLADQA1TH01 and polymarker system) for the skeleton and the suspect’s families. Blood and DNA types analysis of two daughters revealed that their patients have 19 alleles in 9 blood and DNA types. Twelve alleles were admitted in the skeletal remain among presumed 19 alleles. There was no blood and DNA type to deny the mother and daughter relation all of nine types. The skeletal remain was not contradicted from the above-mentioned result though thought daughters’mother.

The brain stem hypoglossal nucleus (HN) is the center of nerves innervating the upper respiratory tract and is related to control of mastication, deglutition, speech and respiration. To elucidate the relationship between asphyxia and the HN, we investigated the change of hypoglossal neurons in cases of hanging, strangulation, smothering, choking, drowning and respiratory failure. Using immunohistochemical techniques, we observed the brain stem HN with antibodies against microtubule-associated protein2(MAP2), muscarinic acetylcholine receptor (mAChR), c-fos gene product (c-Fos) and 72kD heat-shock protein (HSP70). MAP2, a cytoskeletal protein of the neuron, is a marker of neuronal damage. Muscarinic AChR was used as a marker of neuronal membrane and ACh signaling. We employed both HSP70 and c-Fos as markers of stress- or damage-related events. We measured the percentage of immunopositive neurons in total neurons of HN. Drowning produced higher expression of HSP70 and c-Fos than other causes of asphyxia, suggesting that drowning induces more severe damage in HN neurons. Furthermore, it was suspected that neuronal changes in drowning might relate to functions of the HN. These observations indicate that immunohistochemical examination of the brain stem HN could provide useful information for determining the cause of asphyxia.