Agonists at dopamine D2 and D3 receptors are important therapeutic agents in the treatment of Parkinson's disease. Compared with the use of agonists, allosteric potentiators offer potential advantages such as temporal, regional, and phasic potentiation of natural signaling, and that of receptor subtype selectivity. We report the identification of a stereoselective interaction of a benzothiazol ...

Dopamine is important for renal perfusion, natriuresis, and the control of blood pressure. Modulation of the activities of adenylyl cyclase, phospholipase C and protein kinases is involved in the signal transduction pathway of dopamine. Peripheral dopamine receptors are classified as the DA1 and DA2 subtypes on the basis of synaptic localization and their pharmacological profiles. In the kidney...

Cocaine addicts are reported to have decreased numbers of striatal dopamine D2 receptors. However, in rodents, repeated cocaine administration consistently produces hypersensitivity to the psychomotor activating effects of both indirect dopamine agonists, such as cocaine itself, and importantly, to direct-acting D2 receptor agonists. The current study reports a possible resolution to this long-...

BACKGROUND Dopaminergic fibers originating from area A11 of the hypothalamus project to different levels of the spinal cord and represent the major source of dopamine. In addition, tyrosine hydroxylase, the rate-limiting enzyme for the synthesis of catecholamines, is expressed in 8-10% of dorsal root ganglia (DRG) neurons, suggesting that dopamine may be released in the dorsal root ganglia. Dop...

The localization of dopamine stores and the expression and localization of dopamine (DAT) and vesicular monoamine transporters (VMAT) type-1 and -2 and of dopamine D1-like and D2-like receptor subtypes were investigated in rat submandibular, sublingual, and parotid salivary glands by HPLC with electrochemical detection, as well as immunochemical and immunohistochemical techniques. Male Wistar r...

In 1952, Delay and Deniker reported the use of chlorpromazine (Thorazine) to treat psychosis. They initiated an important advance in the treatment of schizophrenia without a clear understanding of the mechanisms underlying the drug's therapeutic effect. In 1963, Carlsson first postulated that the effects of neuroleptics were secondary to dopamine receptor blockade. Also at this time researchers...

In man, non emetic doses of apomorphine elicit a series of behavioural, neurological and psychological changes which are difficult to ascribe to the stimulation of postsynaptic dopamine receptors. Since similar effects are elicited by neuroleptic drugs, the functional changes induced by apomorphine in man might be interpreted as being the result of a decreased dopaminergic activity. The sedatio...

In rat prefrontal cortex (the prelimbic area of medial frontal cortex), the induction of long-term depression (LTD) and long-term potentiation (LTP) of glutamatergic synapses is powerfully modulated by dopamine. The presence of dopamine in the bathing medium facilitates LTD in slice preparations, whereas in the anesthetized intact brain, dopamine released from dopaminergic axon terminals in the...

Intravenous administration of dopamine produced a dose-dependent decrease in lower esophageal sphincter pressure and a dose dependent increase in contractile activity of the body of the esophagus. The threshold dose of dopamine was 0.25 mug/kg, and the effect reached a plateau at about 6 mug/kg. A dose of 6 mug/kg of dopamine produced 83%+/-3 (SE) reduction in the lower esophageal sphincter pre...

All of the components of a complete dopamine system are present within the kidney, where dopamine acts as a paracrine substance in the control of sodium excretion. Dopamine receptors can be divided into D1-like (D1 and D5) receptors that stimulate adenylyl cyclase and D2-like (D2, D3, and D4) receptors that inhibit adenylyl cyclase. All 5 receptor subtypes are expressed in the kidney, albeit in...