Biomaterial Database

Photoaffinity labeling of the angiotensin II receptor. 3. Receptor inactivation with photolabile hormone analogues. 1979

E H Escher, and G Guillemette

It has been shown that the receptor of angiotensin II (AT) in rabbit aorta strips, rat aorta, and rat stomach can be blocked specifically and irreversibly by several photolabile analogues of Sar-Arg-Val-Tyr-Val-His-Pro-Phe ([Sar1]AT) with irradiation. The effectiveness of a photolabel with light of wavelength 365 nm depends on the labeling amino acid (L-4'-nitrophenylalanine, L-4'-diazoniumphenylalanine, or L-4'-azidophenylalanine) and on its position in the peptide (replacing Tyr4 and/or Phe8). The 4'-azido)Phe-containing analogues are all good to fair photoinactivators. Their decreasing order of effectiveness is as follows: [Sar1,(4'-azido)Phe8]AT, [Sar1,(4'-azido)Phe4,8]AT, and [Sar1,(4'-azidoPhe4]AT. The (4'-nitro)Phe analogues show the opposite relation: the good ligand [Sar1,(4'-nitro)Phe8]AT is almost ineffective, but the nonligand [Sar1,(4-nitro)Phe4]AT exhibits good, specific photoinactivation. This can be explained by the existence of a different photolysis pathway for (4'-nitro)Phe: this analogue probably undergoes a multiphoton decay with a long-lived first excited state. A peptide in this state may differ in its pharmacological properties from the ground state and become a ligand.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008297	Male		Males
D009119	Muscle Contraction	A process leading to shortening and/or development of tension in muscle tissue. Muscle contraction occurs by a sliding filament mechanism whereby actin filaments slide inward among the myosin filaments.	Inotropism,Muscular Contraction,Contraction, Muscle,Contraction, Muscular,Contractions, Muscle,Contractions, Muscular,Inotropisms,Muscle Contractions,Muscular Contractions
D009130	Muscle, Smooth	Unstriated and unstriped muscle, one of the muscles of the internal organs, blood vessels, hair follicles, etc. Contractile elements are elongated, usually spindle-shaped cells with centrally located nuclei. Smooth muscle fibers are bound together into sheets or bundles by reticular fibers and frequently elastic nets are also abundant. (From Stedman, 25th ed)	Muscle, Involuntary,Smooth Muscle,Involuntary Muscle,Involuntary Muscles,Muscles, Involuntary,Muscles, Smooth,Smooth Muscles
D009131	Muscle, Smooth, Vascular	The nonstriated involuntary muscle tissue of blood vessels.	Vascular Smooth Muscle,Muscle, Vascular Smooth,Muscles, Vascular Smooth,Smooth Muscle, Vascular,Smooth Muscles, Vascular,Vascular Smooth Muscles
D010777	Photochemistry	A branch of physical chemistry which studies chemical reactions, isomerization and physical behavior that may occur under the influence of visible and/or ultraviolet light.	Photochemistries
D010782	Photolysis	Chemical bond cleavage reactions resulting from absorption of radiant energy.	Photodegradation
D011817	Rabbits	A burrowing plant-eating mammal with hind limbs that are longer than its fore limbs. It belongs to the family Leporidae of the order Lagomorpha, and in contrast to hares, possesses 22 instead of 24 pairs of chromosomes.	Belgian Hare,New Zealand Rabbit,New Zealand Rabbits,New Zealand White Rabbit,Rabbit,Rabbit, Domestic,Chinchilla Rabbits,NZW Rabbits,New Zealand White Rabbits,Oryctolagus cuniculus,Chinchilla Rabbit,Domestic Rabbit,Domestic Rabbits,Hare, Belgian,NZW Rabbit,Rabbit, Chinchilla,Rabbit, NZW,Rabbit, New Zealand,Rabbits, Chinchilla,Rabbits, Domestic,Rabbits, NZW,Rabbits, New Zealand,Zealand Rabbit, New,Zealand Rabbits, New,cuniculus, Oryctolagus
D011945	Receptors, Angiotensin	Cell surface proteins that bind ANGIOTENSINS and trigger intracellular changes influencing the behavior of cells.	Angiotensin Receptor,Angiotensin Receptors,Angiotensin II Receptor,Angiotensin III Receptor,Receptor, Angiotensin II,Receptor, Angiotensin III,Receptor, Angiotensin
D011956	Receptors, Cell Surface	Cell surface proteins that bind signalling molecules external to the cell with high affinity and convert this extracellular event into one or more intracellular signals that alter the behavior of the target cell (From Alberts, Molecular Biology of the Cell, 2nd ed, pp693-5). Cell surface receptors, unlike enzymes, do not chemically alter their ligands.	Cell Surface Receptor,Cell Surface Receptors,Hormone Receptors, Cell Surface,Receptors, Endogenous Substances,Cell Surface Hormone Receptors,Endogenous Substances Receptors,Receptor, Cell Surface,Surface Receptor, Cell