Search PubMed⌕ Search

Biomedical subjects

K N Sharma

Publications and source records attributed to K N Sharma.

At least 37 records · Page 2Linked to original sources
PubMed1986

Effect of selective gastric vagotomy on gustatory behavior in rats.

Gustatory responses were investigated in sham vagotomized (SVgX) and selective gastric vagotomized (VgX) male rats by 1-h single-bottle tests using 3% sucrose, 13% glucose, 0.2% saccharin, 0.9% sodium chloride, 0.16% citric acid, 0.001% quinine sulphate and tap water as test solutions. The intakes of sucrose, glucose, saccharin and sodium chloride were significantly less in VgX rats, compared to SVgX ones. When all these rats were exposed to graded concentrations of sucrose (0.1%, 0.5%, 1% and 5%), a maximum preference was shown to 5% and the least to 0.1% sucrose by both SVgX and VgX rats, even though the VgX rats consumed less than SVgX ones. Vagotomy produced a maximum suppression of 5% sucrose intake, a moderate suppression of 1% and 0.5% sucrose intake and no significant change in the intake of 0.1% sucrose. The results also indicated a probable reduction in the ability of VgX rats to discriminate taste intensities within a close range. Pharmacological blocking of vagal efferents with atropine methyl nitrate (5 mg/kg) did not produce any significant change in the intakes. The possibility of an excitatory input through the gastric vagal afferents selectively influencing the intake of sapid substances is suggested.

Animals↗
PubMed1985

Cardiorespiratory changes following chemical applications to gut serosa.

Application of 0.2-0.3 ml of 1 M ammonium chloride, 100 mM citric acid, 100 mM hydrochloric acid, 1% potassium chloride, 1% ammonium oxalate, 1% oxalic acid, 0.5% sodium hydroxide, 200 micrograms% bradykinin or 20 mg% capsaicin to gastrointestinal serosa produced a fall in blood pressure and inhibition of respiration in hypertensive as well as normotensive rats. In 6 (8%) of the animals studied, a fall in heart rate was also seen which was blocked by atropine. The blood pressure changes were independent of changes in heart rate. After acute abdominal vagotomy, while the respiratory inhibition following chemical application on gut serosa was enhanced, the cardiovascular responses were the same as before. In animals subjected to sympathetic denervation by spinal section at T5, celiac ganglionectomy or splanchnicotomy, a similar application produced an augmented respiratory response while the cardiovascular parameters were unaffected. These results show that the above inhibitions were mediated through the sympathetic afferents and a minor stimulation of respiration, via vagal afferents. The efferent pathway for the cardiac changes seems to be via vagus and the vascular changes via the sympathetics. In chronic vagotomized animals, the same stimulation produced a response similar to that seen in animals with intact vagus. An adaptive response may be operating in chronic animals reverting the status back to normal.

Ammonium Chloride↗
PubMed1978

Gastric chemoceptive projections to fasciculus solitarius and its dipole field structure.

The gastric branch of the vagus nerve, close to the stomach was stimulated electrically and the evoked potentials recorded from the fasciculus solitarius of frog within the stereotaxic coordinates P 4.1-4.6; L 0.5-0.8 and V 0.3-0.5. A predominantly monophasic negative potential, the amplitude (1.0-3.0 mV) of which rises with increase in stimulus strength up to 6 V, could be recorded. From the velocity of conduction (30 m/sec) it appears that the gastric afferent fibres belong to Group A. The depth-recording resulted in the reversal of the negative sign of the potential at depth beyond 180-200 mu. The significance of the appearance of a positive potential and the cellular configuration of the area of fasciculus is discussed in the context of a possible dipole that might exist in the spatial structure from which the depth-recording has been made.

Animals↗
PubMed1975

Cross-cultural differences in simple taste preferences.

A population of Indian laborers who show high preferences for sour and bitter tastes has been studied. Their judgments of taste intensity and pleasantness of sweet and salty stimuli are in accord with European population estimates, which suggests that dietary history may alter preferences for simple taste stimuli without affecting the gustatory system.

Feeding Behavior↗