Excitatory and inhibitory 5-hydroxytryptamine (5-HT) receptors expressed in the isolated porcine uterine muscles.

5-Hydroxytryptamine (5-HT) receptors mediating excitatory and inhibitory actions of 5-HT on contractility of uterine strips from non-pregnant pigs were characterized. Expression of 5-HT(2A) and 5-HT(7) receptors was examined by molecular biological study. 5-HT-containing cells were observed immunohistochemically.

A non-selective cationic channel activated by diacylglycerol in mouse intestinal myocytes.

Application of 1-oleoyl-2-acetyl-sn-glycerol (OAG), an analogue of diacylglycerol (DAG) formed via M(3) muscarinic receptors, induced inward cationic currents via a protein kinase C-independent mechanism and produced membrane depolarization with increased action potential discharges in mouse intestinal myocytes. Outside-out patches from the myocytes responded to OAG with openings of 115-pS channels characterized by a mean open time (O(tau)) of 0.15 ms.

Characterization of prostanoid receptors present on adrenergic neurons innervating the porcine uterine longitudinal muscle.

The cyclooxygenase-prostanoid pathway regulates myometrial contractility through activation of prostanoid receptors on uterine smooth muscles. However, the possible expression of prostanoid receptors on autonomic nerves cannot be excluded completely. The aim of the present study was to clarify the presence of neural prostanoid receptors on adrenergic nerves in the porcine uterine longitudinal muscle.

Muscarinic receptor subtypes involved in carbachol-induced contraction of mouse uterine smooth muscle.

Functional muscarinic acetylcholine receptors present in the mouse uterus were characterized by pharmacological and molecular biological studies using control (DDY and wild-type) mice, muscarinic M2 or M3 single receptor knockout (M2KO, M3KO), and M2 and M3 receptor double knockout mice (M2/M3KO). Carbachol (10 nM-100 microM) increased muscle tonus and phasic contractile activity of uterine strips of control mice in a concentration-dependent manner. The maximum carbachol-induced contractions (Emax) differed between cervical and ovarian regions of the uterus.

Three distinct muscarinic signalling pathways for cationic channel activation in mouse gut smooth muscle cells.

Using mutant mice genetically lacking certain subtypes of muscarinic receptor, we have studied muscarinic signal pathways mediating cationic channel activation in intestinal smooth muscle cells. In cells from M2 subtype-knockout (M2-KO) or M3-KO mice, carbachol (100 microM) evoked a muscarinic cationic current (mI(Cat)) as small as approximately 10% of mI(Cat) in wild-type (WT) cells. No appreciable current was evoked in M2/M3 double-KO cells.