Dramatic and vascular bed-specific hemodynamic changes occur in pregnancy and hypertension of pregnancy (HtP). Because myosin phosphatase (MP) is the primary effector of smooth muscle relaxation and a key target of signaling pathways that regulate vascular tone, we hypothesized that MP expression would be altered in these conditions. The abundance of the targeting/regulatory subunit of MP (MYPT...

The uterine tissue consists of unstriped muscle fibre and ganglia of the sympathetic system imbedded in it. The sacral roots and pelvic nerve do not enter into the composition of the uterine plexus. In the rabbit, irritation of the hypogastric nerve produces vasoconstriction and contraction of the uterus. In cats, stimulation of the hypogastric nerve produces at one time contraction and at othe...

Brown A, Cornwell T, Korniyenko I, Solodushko V, Bond CT, Adelman JP, Taylor MS. Myometrial expression of small conductance Ca -activated K channels depresses phasic uterine contraction. Am J Physiol Cell Physiol 292: C832–C840, 2007; doi:10.1152/ajpcell.00268.2006.—Mechanisms regulating uterine contractility are poorly understood. We hypothesized that a specific isoform of small conductance Ca...

The effects of varying the sodium gradient-either by lowering [Na+]o or by increasing [Na+]i on the electromechanical properties of pregnant rat uterine smooth muscle were studied. In normal tissues, complete removal of external sodium ions (choline, Tris or sucrose as substitutes) induced a strong and maintained contraction which was dependent on the presence of extracellular calcium ions, and...

Blood and extracts of gut of the American cockroach, Periplaneta americana, powerfully stimulate contractions of the isolated rat uterus. The contractions are characterized by long latency and a prolonged relaxation phase having superimposed rhythmic contractions. Evidence indicates that the stimulating factor is not acetylcholine, 5-hydroxytryptamine, histamine, or substance P. The active fact...

Introduction: It is known that anticholinergic agents contribute to improve quality of conventional uterine MR images with suppression of intestinal motion. Similar to intestine, uterine myometrium consists of smooth muscles and rhythmical motion is known as uterine peristalsis. However, the effect of the anticholinergic agents to suppress uterine contractility has been shown to be weaker compa...

There is now considerable evidence for the involvement of K+ channels in nitric oxide (NO) induced relaxation of smooth muscles including the myometrium. In order to assess whether apamin-sensitive K+ channels play a role in NO - induced relaxation of the human uterus, we have studied the effect of specific blockers of these channels on the relaxation of myometrium from non-pregnant women. In v...

We have tested the hypothesis that increased gap junctional communication contributes to the augmented endothelium-dependent vasodilation in pregnancy. Contractile force and connexin43 expression were measured in aortic rings from nonpregnant and pregnant rats. Norepinephrine-constricted aortas from pregnant rats were more sensitive to acetylcholine, but not to sodium nitroprusside, compared wi...

purpose :   this study was designed to compare the effects of two different relaxation techniques, namely progressive muscle relaxation (pmr) and autogenic relaxation (agr) on moods of young soccer players . methods :   sixteen adolescent athletes (mean age: 14.1 ± 1.3) received either pmr or agr training. using profile of mood states-adolescents, their mood states were measured one week before...