Citalopram, a serotonin reuptake inhibitor, and brain ischemia in SHR.
The effects of citalopram, a serotonin (5-HT) reuptake inhibitor, on cerebral blood flow (CBF) and concentration of 5-HT and its metabolite were investigated in spontaneously hypertensives rats (SHR) subjected to forebrain ischemia. Cerebral ischemia was induced by bilateral carotid artery occlusion. The concentration of the 5-HT metabolite, 5-hydroxyindoleacetic acid (5-HIAA), increased during cerebral ischemia in most brain regions examined, while that of 5-HT increased only in the frontal cortex and the striatum. Citalopram restored the 5-HIAA concentrations to the preischemic normal levels. Citalopram had no effect on the cortical CBF, before and during ischemia. These results suggest that citalopram attenuates ischemia-induced hypermetabolism of 5-HT in the brain. The effects of citalopram are independent of hemodynamic factors including cerebral blood flow, and are likely to be mediated by a direct inhibition of the neuronal 5-HT reuptake system.
Nagao
T
T
Second Department of Internal Medicine, Kyushu University, Fukuoka, Japan.
Ibayashi
S
S
Sadoshima
S
S
Izumi
J
J
Fujishima
M
M
D000818:Animals; D001794:Blood Pressure / Q000187:drug effects / Q000502:physiology; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology; D001923:Brain Chemistry / Q000187:drug effects; D002545:Brain Ischemia / Q000378:metabolism / Q000503:physiopathology*; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology; D015283:Citalopram / Q000494:pharmacology*; D005260:Female; D006897:Hydroxyindoleacetic Acid / Q000378:metabolism; D006973:Hypertension / Q000235:genetics / Q000378:metabolism / Q000503:physiopathology*; D051381:Rats; D011918:Rats, Inbred SHR; D015656:Respiratory Mechanics / Q000187:drug effects / Q000502:physiology; D012701:Serotonin / Q000378:metabolism; D017367:Selective Serotonin Reuptake Inhibitors / Q000494:pharmacology*
D015283:Citalopram; D006897:Hydroxyindoleacetic Acid; D012701:Serotonin; D017367:Selective Serotonin Reuptake Inhibitors