Locomotor response of nialamide pretreated old rats to intraaccumbens dopamine.
The objective of this study was to determine the locomotor activity response of young (6 month), mature (15 month), and old (26 month) rats to bilateral intraaccumbens injections of dopamine after pretreatment with nialamide. Young and mature rats responded to dopamine with high rates of activity, while old rats either did not respond at all or responded with a lower intensity of activity. In contrast, the response of old rats to dopamine or ergometrine alone or to dopamine after pargyline pretreatment was not less than that of mature and young rats. These results suggest that the attenuated response of old rats to dopamine after nialamide pretreatment is not due to a decrease in dopamine receptor activity, but appears to be due to some unique property of nialamide in these animals. However, the reduced response of old rats to dopamine was not due to the inability of nialamide to inhibit monoamine oxidase, since nialamide completely inhibited the activity of this enzyme in the nucleus accumbens of old rats.
D000375:Aging; D000818:Animals; D004298:Dopamine / Q000008:administration & dosage / Q000494:pharmacology*; D004874:Ergonovine / Q000494:pharmacology; D007267:Injections; D008297:Male; D008995:Monoamine Oxidase / Q000378:metabolism; D009043:Motor Activity / Q000187:drug effects*; D009526:Nialamide / Q000494:pharmacology*; D009714:Nucleus Accumbens / Q000033:anatomy & histology / Q000201:enzymology; D010293:Pargyline / Q000494:pharmacology; D051381:Rats; D011916:Rats, Inbred F344; D013997:Time Factors
D010293:Pargyline; D008995:Monoamine Oxidase; D009526:Nialamide; D004298:Dopamine; D004874:Ergonovine