A comparison of the hypotensive effects of Met-enkephalin in normotensive and spontaneously hypertensive rats.
To elucidate the role of Met-enkephalin in the hypertension in spontaneously hypertensive rats, the depressor response to Met-enkephalin was compared between normotensive (Wistar) and spontaneously hypertensive rats by administration of bestatin (1.25 mg) as a component of a mixture of enkephalinase inhibitors. All experiments were performed under anesthesia by intraperitoneal injection of pentobarbital (50mg/kg). Catheters were connected to the arterial and venous lines for blood pressure recording and administration of drugs. Hypotensive effects of injected Met-enkephalin were noticeably enhanced by administration of bestatin compared with pre-bestatin responses at each dose of Met-enkephalin(10, 25, 50, and 100n mol). We could not find any statistically significant difference between blood pressure responses to 25n mole Met-enkephalin in Wistar and spontaneously hypertensive rats both before and after administration of bestatin. Our present study dose not suggest the active role of Met-enkephalin in the hypertension of spontaneously hypertensive rats.
Nomura
S
S
Department of Obstetrics and Gynecology, Nagoya University School Medicine, Japan.
Mizutani
S
S
Kurauchi
O
O
Furuhashi
M
M
Kasugai
M
M
Narita
O
O
Tomoda
Y
Y
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology; D001794:Blood Pressure / Q000187:drug effects*; D004744:Enkephalin, Methionine / Q000494:pharmacology*; D006973:Hypertension / Q000503:physiopathology*; D007930:Leucine / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D051381:Rats; D011918:Rats, Inbred SHR; D011919:Rats, Inbred Strains
D000903:Antibiotics, Antineoplastic; D004744:Enkephalin, Methionine; D007930:Leucine; C012211:ubenimex