On noble distance

The vessels are deprived of parasympathetic nerves. They rule the sympathetic nervous system, autoregulation and hormones. Sympathetic impulses come to vascular muscles of vasomotor centers through the sympathetic ganglia, which are the substations for ascending and descending pulses, small district centrically with limited powers, but in principle simplified likeness vasomotor center. This ganglion evaluates all of the ascending and descending information and is authorized to amend them accordingly the situation that has developed in the internal environment, for in the ganglion "bottom" receives signals from receptors (mainly textile)and cysts can request more blood than let him vasomotor Ministry; in some situations ganglion is entitled to make its own decision. All this can be realized exclusively reflex by, as a reflex from interception may withdraw not only in the centres, but in the ganglia, and centrifugal vasomotor signals can be corrected and supplemented in accordance with the needs of local places.
We offer the reader to explore with us the work of two of sympathetic ganglia cat: caudal mesenteric and upper neck. Caudal is situated towards the tail (the specialities available include - tail); in humans it is inferior mesenteric ganglion. This cyst in one of the chapters analyzed blindfolded Century N. Chernihiv. We will carry out electrophysiological analysis of both the nerve nodes, determine the impact of their work on the circulation and see how it all depends on age.
Mesenteric ganglion sits on artery of the same name near its branching off the aorta. It consists of several (usually two) nerve nodes, interconnected nerve commissures. Everyone gets twigs from the sympathetic chain and solar plexus and gives nerves, the main of which are the lower the nerves going to the vessels and organs of the pelvis. Only about a dozen mixed branches, bringing and carrying signals.
Write impulsaciu hypogastric nerve on film, without damaging the nerve. This total impulses in the newborn kitten has on average frequency of about 17 Hz and the voltage of 10 mV. With age both doubled, increasing evenly and reaching its peak by the time of puberty.
At the upper cervical sympathetic ganglion, on the contrary, the voltage and frequency pulsation immediately after birth is very high - as in mesenteric ganglia eight cats, and in adult cats - attenuated. A lower rate of pulsation cervical ganglion is not the result of his laziness that comes with age, but the result of active process, i.e. the brake of influence of the higher nervous vegetative centers. The day kitten bodies of the front half of the body sufficiently developed: the brain, heart, lungs - are all ready to work, everyone has the pelvis organs and intestines are weak: the baby can eat only milk, can not reproduce and even empty the bowel and bladder through the mother. Accordingly vessels in the area mesenteric ganglion with age, strongly developed and require more complex regulation, and in front of the body is constant oversight of vessels is not required. The heart and brain, by contrast, are becoming more independent from the system of regulation, and the regime they have very special.
If you cut one hypogastric nerve disables part of pulses of interoception half of organs and vessels of the pelvis. The Central segment of the hypogastric nerve is recorded only what ganglion dictates his charges. If the cat adult, the ganglion takes much more commands than before transection. This increased activity continues after transection some branches of the cyst, still some, but not all, of course. After transection approximately half of all branches impulses back to the original intensity. Now every next transection causes a decrease in the flow of information to the organs and vessels of the pelvis, and transection last sprigs not cease impulsaciu: ganglia, as vasomotor center, does not have its own activity, but only a reflex, but still misses the "transit" impulses of neurons that this ganglia not interrupted by a synapse (see Fig. 3).
So, moderate decrease of information coming in ganglion from all sides - center and the periphery, enhances its own activity, then everything goes on the contrary, the impulses weaken and ganglion fades. It should be on our previous observations "working point" arterial pressure and vascular tone, and hence sympathetic activity is your cat in the saddle between the humps of a camel. Do not be lazy again to look at the pictures.
We have another possibility is that instead of shutdown activity addressed to the ganglion, strengthen, irritating one of nerve branches or inflating one of the hollow organs of the pelvis or the large intestine. "Shortage" is immediately compensated: mild irritation im ripple increases, strong decreases, super-high - comes braking ganglion held with the termination of exposure. Again camel. The sympathetic ganglia (mesenteric) adult cats works on the same principle that her vasomotor center, i.e. detects the ability to be actuated or to hinder, depending on the force of the impact. Pulse effect, isn't it? If we compare the electrical activity of the cyst with blood flow in the artery on which it sits, you can verify that between one and another - direct dependence (see Fig. 3).
So, the M-shaped relationship between the impulses on the input and output characteristic of and sympathetic to the ganglion. But ganglion by itself, if it is not in Union with his spinal center, unable to provide local vascular tone. This failure manifests itself in traumatic breaks the spinal cord between the thoracic and lumbar segments. In addition to clear the paralysis of the legs and evacuation dysfunction of the pelvic organs, such patients occurs full orthostatic instability circulation: just a little lift the headboard, as it comes out. But let us continue the experiment.
It turns out that the younger the animal is, the smaller the number caudal mesenteric ganglion pulses need to disable to stop the activity of the cyst. The newborn kitten ganglion stops impulsivity after crossing three-four nerve branches. Despite the restructuring, two-dependence is saved, but what is surprising: if an adult animal tone of the vessel is the higher, the more intense coming to him impulses, in young kittens - on the contrary: the more the vessel firing of nerve impulses, the lower its tone. Thus, the M-shape curve tone is dependent on the activity of the cyst.
All age dynamics, which we have traced in time "backwards", shows that the kitten "the working point of regulation is on the left hump curve, like frogs and turtles, in full accordance with the basic biogenetic law of Haeckel: evolutionary development in General is repeated in individual development.
In order to get convinced in the rightness of its findings, remember studied the usual way (irritation nicotine off novocaine) the dependence of arterial pressure on the activity of receptors of the heart cats in age aspect. And in this case, we have a match with experiments on mesenteric ganglia. "The point" with age sliding on camel back to the right, from the left hump to the saddle, which this point is by the time adulthood cats. Thus, at the level of the cyst" and at the "system level" solution of the problem is the same.
Let's add that a growing denervation superior cervical ganglion by successive transection of its branches leads to the same result - the complete loss of activity, which for this ganglion, and for higher vasomotor centers is not automatic, own, and is called from outside coming impulses reflex. Hence, the epigraph to Chapter does not accurate. Ganglia - no Prince in its segment, it is only a computer with multiple inputs and outputs (as, however, and the higher centres).