Involvement of renin-angiotensin system in hypertensive effect of cadmium in rats.
Role of renin-angiotensin system in hypertension induced by cadmium chloride (CdCl2) in rats has been investigated. Intravenous administration of CdCl (1 mg/kg) produced a biphasic response i.e. a transient fall followed by a marked and consistent rise in blood pressure. The peak hypertensive effect was accompanied by raised PRA levels. Pretreatment with captopril (1 mg/kg, i.v.) losartan (1 mg/kg, i.v.) or captopril + losartan attenuated the pressor response to Cd by 62%, 42% and 100% respectively in separate groups. Central administration of Cd (10 micrograms/rat, i.c.v.) showed a biphasic response similar to that observed after i.v. route. However, it was not accompanied by raised PRA levels. Prior treatment with losartan (10 micrograms/rat, i.c.v.) completely abolished the pressor response to Cd (i.c.v.) whereas it was not affected significantly by captopril (10 micrograms/rat, i.c.v.). On the other hand, centrally administered losartan only partially reduced the pressor response to i.v. Cd. The results are discussed in light of a differential involvement of central vs peripheral renin-angiotensin system in the hypertensive effect of Cd.
Lall
S B
SB
Department of Pharmacology, All-India Institute of Medical Sciences, Ansari Nagar, New Delhi, India.
Peshin
S S
SS
Gulati
K
K
Khattar
S
S
Das
N
N
Seth
S D
SD
D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology; D002104:Cadmium / Q000633:toxicity*; D002216:Captopril / Q000494:pharmacology; D006973:Hypertension / Q000139:chemically induced* / Q000503:physiopathology; D019808:Losartan / Q000494:pharmacology; D008297:Male; D051381:Rats; D012083:Renin / Q000097:blood; D012084:Renin-Angiotensin System / Q000187:drug effects* / Q000502:physiology*; D013997:Time Factors
D000959:Antihypertensive Agents; D002104:Cadmium; D002216:Captopril; D012083:Renin; D019808:Losartan