0000000000338032
AUTHOR
Josefina Magraner
showing 5 related works from this author
Effects of Mn2+ on the responses induced by different spasmogens in the oestrogen-primed rat uterus
1997
Abstract We investigated the effect of Mn 2+ on the mechanical responses evoked by high K + (60 mM) or low Na + (25 mM) solutions, oxytocin and neurokinin A in the oestrogen-primed rat uterus. In a Ca 2+ -free, Mn 2+ (0.54 mM)-containing solution, high K + or low Na + solutions produced contractions of smaller amplitude than those observed in a normal Ca 2+ (0.54 mM) solution, which were abolished by nifedipine (1 μM). Oxytocin (1 μM) and neurokinin A (1 μM, in the presence of phosphoramidon 1 μM) evoked nifedipine-insensitive contractile responses similar to (oxytocin) or smaller (neurokinin A) in amplitude than those observed in Ca 2+ (0.54 mM)-containing solution. In strips loaded with C…
Characterization of tachykinin receptors in the uterus of the oestrogen-primed rat
1998
The aim of our study was to characterize the tachykinin receptor population in the oestrogen-primed rat uterus. For this purpose, we investigated the receptor type(s) responsible for tachykinin-induced contraction of longitudinally-arranged smooth muscle layer. The effects of substance P (SP), neurokinin A (NKA), neurokinin B (NKB) and several of their analogues with well-defined selectivities for tachykinin NK1, NK2 and NK3 receptors were studied and their inhibition by the selective nonpeptide tachykinin receptor antagonists (S)1-(2-[3-(3,4-dichlorophenyl)-1-(3-isopropoxyphenylacetyl)piperidin-3-yl]ethyl)-4-phenyl-1-azoniabicyclo[2.2.2]octane chloride (SR 140333, NK1-selective), (S)-N-met…
Mechanism of vascular relaxation by thaligrisine
2000
Abstract In the present study we examine the mechanism by which thaligrisine, a bisbenzyltetrahydroisoquinoline alkaloid, inhibits the contractile response of vascular smooth muscle. The work includes functional studies on rat isolated aorta and tail artery precontracted with noradrenaline or KCl. In other experiments rat aorta was precontracted by caffeine in the presence or absence of extracellular Ca 2 +. In order to assess whether thaligrisine interacts directly with calcium channel binding sites or with α-adrenoceptors we examined the effect of the alkaloid on [ 3 H]-(+)- cis diltiazem, [ 3 H]-nitrendipine and [ 3 H]-prazosin binding to cerebral cortical membranes. The functional studi…
Regulation by oestrogens of tachykinin NK3 receptor expression in the rat uterus.
1997
The expression of the tachykinin NK3 receptor and its regulation by ovarian steroids were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) in uteri from ovariectomized rats. A single transcript corresponding to the 325-bp product expected for the tachykinin NK3 receptor was detected in uteri from olive oil-treated (control) ovariectomized rats. The level of tachykinin NK3 receptor mRNA in progesterone-treated animals was similar to that observed in uteri from control ones. Tachykinin NK3 receptor mRNA levels were significantly smaller in uteri from oestrogen-treated ovariectomized rats, with approximately a 32-fold decrease. These findings suggest that oestrogen, but not…
Changes in the Expression of Tachykinin Receptors in the Rat Uterus During the Course of Pregnancy1
2001
In the mammalian female reproductive tract, tachykinin neuropeptides, such as substance P (SP), are localized to a population of sensory fibers and their precise physiological role is still unknown. The aim of the present study was to characterize the population of tachykinin receptors in the pregnant rat uterus and to assess their regulation during the course of pregnancy and after delivery. The expression of the tachykinin NK(1) receptor (NK(1)R), the tachykinin NK(2) receptor (NK(2)R), and the tachykinin NK(3) receptor (NK(3)R) in uteri from rats at different stages of pregnancy and on Day 1 postpartum was investigated by using a semiquantitative reverse transcription-polymerase chain re…