Recovery of beta-receptors and adenylate cyclase from desensitization induced by short term heat exposure in rat parotid glands.
1. The recovery of rat parotid beta-adrenergic receptors (beta-AR) and adenylate cyclase (AC) from heat (33 degrees C)-induced desensitization was studied. 2. Down-regulated cell surface beta-AR and AC activity in response to isoprenaline (IPR) returned to the control level 120 hr after the termination of heat exposure. 3. However, beta-AR in parotid crude membranes increased over the control level for 48-120 hr. 4. Coupling between beta-AR and G protein(s) was attenuated at 120 hr. 5. These data suggest that beta-AR on the cell surface, but not those internalized, can transduce biological responses.
Department of Pharmacology, Tokyo College of Pharmacy, Japan.
H
H
Fujinami
T
T
Komabayashi
T
T
Izawa
T
T
Nakamura
K
K
Suda
T
T
Minoru
D000067956:Adenylyl Cyclase Inhibitors; D000262:Adenylyl Cyclases / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D001834:Body Water / Q000378:metabolism; D005576:Colforsin / Q000494:pharmacology; D015536:Down-Regulation / Q000187:drug effects; D004837:Epinephrine / Q000097:blood; D019204:GTP-Binding Proteins / Q000378:metabolism; D006153:Guanosine Diphosphate / Q000378:metabolism; D006358:Hot Temperature / Q000009:adverse effects*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D015636:Magnesium Chloride / Q000494:pharmacology; D008297:Male; D008566:Membranes / Q000201:enzymology / Q000378:metabolism; D009638:Norepinephrine / Q000097:blood / Q000378:metabolism; D010306:Parotid Gland / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011943:Receptors, Adrenergic, beta / Q000187:drug effects / Q000502:physiology*
D000067956:Adenylyl Cyclase Inhibitors; D011943:Receptors, Adrenergic, beta; D015636:Magnesium Chloride; D006153:Guanosine Diphosphate; D005576:Colforsin; D019204:GTP-Binding Proteins; D000262:Adenylyl Cyclases; D007545:Isoproterenol; D009638:Norepinephrine; D004837:Epinephrine