摘要:

WE have shown previously that sympathetic ganglia from genetically hypertensive Otago Wistar (GH) rats contain fewer neurons than those of normotensive animals and are heavily innervated by substance P-containing axons. In adult GH rats treated over days 1–7 of postnatal life with 10 μg/rat/day of nerve growth factor (NGF) s.c., ganglion cell numbers were similar to those of normotensive rats. By contrast, NGF treatment of neonatal normotensive animals did not affect ganglion cell numbers. In NGF-treated GH animals, the numbers of substance P-positive axons were substantially reduced relative to age-matched controls. We conclude that the abnormalities seen in ganglia of GH rats may involve a perinatal deficiency of a nerve growth factor.

ISSN:0959-4965    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

THE effects of intracerebroventricular administration of dermorphin (μ agonist) and dermenkephalin ( agonist) were studied at the electrocorticographic (ECoG) and electromyographic (EMG) levels in free-moving rats. A very low dose of dermorphin (125 pmol) induced ECoG spiking, occasional myoclonic jerks, wet-dog shakes and catalepsy. In addition, electrical seizures were triggered with doses of 250 to 500 pmol. These signs were reversed by an i.p. injection of naloxone (1 mg kg-1). However, no epileptic-like phenomena were seen after administration of dermenkephalin up to 1 nmol. These results indicate that μ but not receptors are involved in the epileptogenic effect of intraventricularly administered opiates.

ISSN:0959-4965    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

THE present study examined the effect of pre-exposure to a moderate dose of caffeine (20 mg kg-1) on the acquisition of self-administration of cocaine (0.125 mg kg-1/infusion or 0.25 mg kg-1/infusion) in the rat. Rats pre-exposed to caffeine acquired self-administration more rapidly. Furthermore, sensitization to cocaine's reinforcing effects was accompanied by an increase in the neurochemical response of the mesolimbic dopamine system to an acute injection of cocaine (10 mg kg-1, i.p.) as measured byin-vivomicrodialysis. Thus, the data suggest that exposure to caffeine can increase the reinforcing effects of cocaine, possibly via an enhanced response of the mesolimbic dopamine system.

ISSN:0959-4965    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

PUTAMEN nuclei were assessed in 36 normal volunteers using magnetic resonance imaging and a systematic sampling method. There was a significant decrease in the volume of the putamen nuclei with advancing age (r= −0.74,p< 0.0001), and an associated decline in the volume of the caudate nuclei (r= 0.60,p< 0.0001). The implications of these findings in age-associated motor abnormalities are discussed.

ISSN:0959-4965    

出版商:OVID    

年代:1991

数据来源: OVID

摘要:

THE present study was undertaken to evaluate the neurotoxic effects of the organophosphate, phosphamidon, on glutathione-S-transferase (GST) activity and concentration of sulphhydryl groups, and to study the possible protection against these effects by the simultaneous administration of the antioxidant, acetylhomocysteine thiolactone, commonly known as citiolone. Significant depletion was observed in the GST activity as well as in the level of total and non-protein bound sulphhydryl groups in various CNS regions of phosphamidon-intoxicated rats. When citiolone was administered alone, there was a remarkable elevation in GST activity. However, significant protection against GST inhibition was observed when phosphamidon and citiolone were administered simultaneously.

ISSN:0959-4965    

出版商:OVID    

年代:1991

数据来源: OVID