|
KMID : 0378019630060010093
|
|
New Medical Journal
1963 Volume.6 No. 1 p.93 ~ p.111
|
|
|
Effects on Mortilities of Digestive Tract Induced by an Electrical Stimulation on Cat´s Hypothalamus
|
|
|
|
|
Abstract
|
|
|
The effect of continuous electrical stimulation of different regions of the hypothalamus through stereotaxically oriented electrodes upon gastrointestinaltmotili ties have been investigated in acute experiments in cats.
Considerable amount of experimental studies for theediscovering hypothalamic function has been made by many authors during past decades.
It became apparent from these investigations that the hypothalamus played a specific and prominent role in the regulation of autonomic nervous function, particularly gastrointestinal motility.
Little information however has been available on synchronous `effects on motilities of different part of whole digestive tract.
In the present studies, an attempt was made tol investigate the changes of motilities at different levels of digestive tract following a longlasting electrical stimulation of various hypothalamic nuclei.
50 cats, weighing between 3.5 and 4.3 kg were used. The animals were fasted for 24 hours before the experiment. The initial light ether anesthesia was necessary in order to fix the animal into the specially designed stereotaxic apparatus which could easily be arranged in the light of stereotaxic atlas of the diencephalon of the cat by jasper and Ajmone-Marsan. The parameters of stimulation were 3 volts, 5 msec. in duration and at a frequency of 20 cps. The stimulus has lasted continuously as long as the animal expired. The method of the Simultaneous Multi-recording System which also was devised by the author permits direct recording of motilities simultaneously at five to seven levels of digestive tract. The intraluminal pressures were transmitted through fine polyethylene tubes to the recorder and the balloons which were inserted into the digestive lumen through a small incision were filled with water keeping a pressure of 10 to 30 cm/H2O.
By giving the continuous electrical stimulation to the different nuclei of hypothalamus the following results were observed:
1. No animals could be survived longer than 14 hours with a continuous stimulation anywhere on hypothalamus. Maximum mean longevity was 10 hours and 19 minutes with the stimulation on the region
between ventromedial hypothalamus and lateral hypothalamus. Minimum mean longevity was 4 hours and 42 minutes with the stimulation on posterior hypothalamus.
2. Continuous stimulation of posterior hypothalamus and ventromedial hypothalamus resulted in active stress reaction while the stimulation on anterior hypothalamus and lateral hypothalamus made active sleep reaction.
3. Continuous stimulation of the anterior hypothalamus resulted in colonic and rectal hypermotility with
occasional appearance of giant peristaltic wave the pressure of which was 100 to 180 mm/HzO.
4. Continuous stimulation of ventromedial hypothalamus resulted in moderate degree of hypermotility at the level of cardia, pylorus and ileum.
5. With continuous lateral hypothalamic stimulation there observed a frequent gastric hypermotility, gastric hemorrhages(80%) and gastric erosions(50%).
6. Continuous stimulation of the region between ventromedial nucleus and lateral hypothalamus disclosed occasional alternate hypermotility between upper gastrointesinal tract and recto-colonic tract.
7. Generalized lower tone of the digestive tract with occasional minor peristaltic waves at the level of stomach, colon and rectum noted after the continuous stimulation on posterior hypothalamus.
8. With the continuous vagus stimulation there observed no hypermotilities of digestive tract as noted after the stimulation of anterior and lateral hypothalamic nuclei.
|
|
|
KEYWORD
|
|
|
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
|
|