title: General pharmacology of ergot alkaloids.
abstract: Ergot alkaloids possess a wide and divergent spectrum of central and peripheral pharmacodynamic actions. They interfere with different receptor sites to stimulate and/or inhibit effector structures. The concept of partial agonism on alpha-adrenoreceptors has replaced the ancient hypothesis of direct stimulation of vascular and uterine smooth muscle. The mechanisms which are considered to be relevant for the therapeutic use of dihydroergotamine, a potent drug increasing venous tone, and of bromocriptine, a specific inhibitor of prolactin secretion, are discussed in more detail.
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002415:Cats; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D010064:Embryo Implantation / Q000187:drug effects; D004876:Ergot Alkaloids / Q000008:administration & dosage / Q000494:pharmacology*; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D010060:Ovulation / Q000187:drug effects; D011388:Prolactin / Q000378:metabolism; D011817:Rabbits; D051381:Rats; D011942:Receptors, Adrenergic, alpha / Q000187:drug effects; D012636:Secretory Rate / Q000187:drug effects; D014661:Vasoconstriction / Q000187:drug effects
chemical_list: D004876:Ergot Alkaloids; D011942:Receptors, Adrenergic, alpha; D011388:Prolactin