Alteration in Ca2+/calmodulin-sensitive adenylyl cyclase activity in the hippocampus of stroke-prone spontaneously hypertensive rats.
This study examined the function of adenylyl cyclase (AC) activity in the hippocampus and cerebral cortex of the stroke-prone spontaneously hypertensive rat (SHRSP). Male SHRSP (8-week-old and 25-week-old) were used for the experiments, and age-matched Wistar-Kyoto rats (WKY) were used as a genetic control. Basal, forskolin-, and GppNHp-stimulated AC activities were not different between SHRSP and WKY in the 8-week-old and 25-week-old groups. Ca2+/calmodulin-sensitive AC activity in hippocampal and cerebral cortex membranes was significantly lower in 25-week-old SHRSP than in age-matched WKY, but it was not in the 8-week-old group. These results suggest that the function of Ca2+/calmodulin-sensitive, presumably type I, AC was impaired in the brain of SHRSP. Such dysfunction of AC possibly contributes to the behavioral impairment reported in passive avoidance tasks in SHRSP.
Hatta
S
S
Department of Pharmacology, School of Medicine, Sapporo Medical University, Japan.
Togashi
H
H
Saito
H
H
Saito
T
T
Ohshika
H
H
D000262:Adenylyl Cyclases / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D002147:Calmodulin / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects / Q000201:enzymology; D002561:Cerebrovascular Disorders / Q000201:enzymology*; D005576:Colforsin / Q000494:pharmacology; D006624:Hippocampus / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011921:Rats, Inbred WKY; D012680:Sensitivity and Specificity; D013268:Stimulation, Chemical
D002147:Calmodulin; D005576:Colforsin; D000262:Adenylyl Cyclases; D002118:Calcium