Biomaterial Database

Investigations into the nature of alpha 2-adrenoceptors in rat tail arteries. 1985

J F Marwood, and K L Chapman, and S J Armsworth, and G S Stokes

In rat isolated perfused tail arteries, dose-response curves were established for the vasopressor effects of phenylephrine (alpha 1-adrenoceptor agonist), clonidine (alpha 1- and alpha 2-adrenoceptor agonist), clonidine in the presence of 10(-7) mol/l prazosin (alpha 2-agonist), and BHT-920 (alpha 2-agonist). The ED50 values were: phenylephrine 1.85 X 10(-10) mol; clonidine 6.3 X 10(-10) mol; clonidine + prazosin 3.2 X 10(-6) mol; BHT-920 6.1 X 10(-6) mol. The arterial reactivity to BHT-920 was stable only after 4-5 h of perfusion. Responses to BHT-920 were not antagonized by yohimbine (alpha 2-adrenoceptor antagonist) but were antagonized by low concentrations of prazosin (alpha 1-adrenoceptor antagonist). These data constitute conflicting evidence regarding the existence of alpha 2-adrenoceptors in rat tail arteries. The data are consistent with the proposal that there are two recognition sites on alpha 1-adrenoceptors; phenylephrine and BHT-920 may stimulate different sites on alpha 1-adrenoceptors.

UI	MeSH Term	Description	Entries
D008297	Male		Males
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
D010477	Perfusion	Treatment process involving the injection of fluid into an organ or tissue.	Perfusions
D011919	Rats, Inbred Strains	Genetically identical individuals developed from brother and sister matings which have been carried out for twenty or more generations or by parent x offspring matings carried out with certain restrictions. This also includes animals with a long history of closed colony breeding.	August Rats,Inbred Rat Strains,Inbred Strain of Rat,Inbred Strain of Rats,Inbred Strains of Rats,Rat, Inbred Strain,August Rat,Inbred Rat Strain,Inbred Strain Rat,Inbred Strain Rats,Inbred Strains Rat,Inbred Strains Rats,Rat Inbred Strain,Rat Inbred Strains,Rat Strain, Inbred,Rat Strains, Inbred,Rat, August,Rat, Inbred Strains,Rats Inbred Strain,Rats Inbred Strains,Rats, August,Rats, Inbred Strain,Strain Rat, Inbred,Strain Rats, Inbred,Strain, Inbred Rat,Strains, Inbred Rat
D011942	Receptors, Adrenergic, alpha	One of the two major pharmacological subdivisions of adrenergic receptors that were originally defined by the relative potencies of various adrenergic compounds. The alpha receptors were initially described as excitatory receptors that post-junctionally stimulate SMOOTH MUSCLE contraction. However, further analysis has revealed a more complex picture involving several alpha receptor subtypes and their involvement in feedback regulation.	Adrenergic alpha-Receptor,Adrenergic alpha-Receptors,Receptors, alpha-Adrenergic,alpha-Adrenergic Receptor,alpha-Adrenergic Receptors,Receptor, Adrenergic, alpha,Adrenergic alpha Receptor,Adrenergic alpha Receptors,Receptor, alpha-Adrenergic,Receptors, alpha Adrenergic,alpha Adrenergic Receptor,alpha Adrenergic Receptors,alpha-Receptor, Adrenergic,alpha-Receptors, Adrenergic
D004305	Dose-Response Relationship, Drug	The relationship between the dose of an administered drug and the response of the organism to the drug.	Dose Response Relationship, Drug,Dose-Response Relationships, Drug,Drug Dose-Response Relationship,Drug Dose-Response Relationships,Relationship, Drug Dose-Response,Relationships, Drug Dose-Response
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D001381	Azepines	Seven membered heterocyclic rings containing a NITROGEN atom.	Hexamethyleneimines
D013623	Tail	An extension of the posterior of an animal body beyond the TORSO.	Tails
D014661	Vasoconstriction	The physiological narrowing of BLOOD VESSELS by contraction of the VASCULAR SMOOTH MUSCLE.	Vasoconstrictions