The neural feedback system controlling tongue muscle activities was studied in the decerebrate cat.
Spontaneous activities were detected from some muscular fibers of the tongue. The discharges of some fibers in the tongue retractors were increased and those in the tongue protruders were decreased by forward stretch of the tongue. These responses were not affected by anesthesia of the tongue surface. However, the responses completely disappeared after dissection of the lingual or glossopharyngeal nerve.
In the lingual and glossopharyngeal nerves, a few fibers were detected to respond to stretch of the tongue. This response was slowly adaptive and the frequency of impulses from the nerve fibers was increased in proportion to the intensity of tongue stretching.
The activity of several spots in the sensory nucleus of trigeminal nerve, in the nucleus of solitary tract, in the dorsal nucleus of vagal nerve, in the bulbar reticular formation and in the nucleus of hypoglossal nerve was activated by stretch of the tongue. On the contrary, the activity of some spots in the hypoglossal nucleus was inhibited.

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The mode of sweating during night sleep was investigated with a polygraphical method, in special reference to changes of its rate in association with EEG pattern. The results were compared with those made in daytime sleep.
While in general the rate of thermogenic sweating was closely associated with EEG depth of sleep in daytime sleep, association between the two phenomena was not so close in night sleep, especially in later sleep cycles. Night sleep was also characterized by a downward overall trend of sweat rate. Those significant differences in the mode of thermogenic sweating between daytime and nocturnal sleep could in part be attributed to diurnal variations of body temperature, but appear to depend more definitely upon differences in the character of sleep. However, the latter per se may be caused by the mechanisms controlling the diurnal body rhythm.
Our observations reveal also that, although in general psychogenic sweating was absent during sleep, it could appear during paradoxical sleep in association with dreams accompanied by emotional excitement, and also as a manifestation of arousal response during sleep

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“Hybridization” of adult human and canine hemoglobins is greatly depressed by the deoxygenation, which suggests that the strength and/or the nature of the inter-chain linkages may undergo a reversible and profound alteration dependent upon the ligand binding. A non-linear relationship is observed between the extent of the “hybridization” and that of the oxygenation, which implies that the above stated alteration in the quaternary structure of hemoglobin proceeds in a non-straightforward manner with the ligand binding.

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1. The contractility and transmembrane action potential (AP) of the isolated left superior vena cava (LSVC) or the inferior vena cava (IVC) proximal to the heart of the rabbit were studied in the presence of various drugs: epinephrine (Epin.); norepinephrine (Norep.); isoproterenol (Isop.); propranolol (Prop.); acetylcholine (Ach.); atropine; ouabain, by usinga stra in gauge and microelectrodes. The results were compared with those obtained from the isolated left atrium (LA).
2. Epin. and Norep.(3.3×10^-6 g/ml) produced increase in the twitch tension and slight prolongation in the AP-duration of the LSVC. Isop.(1.3×10^-6 g/ml), conversely, shortened AP-duration in spite of increase in the twitch tension. The contraction and potential changes produced by Epin. on the LA were virtually similar to those on the LSVC.
3. Prop.(1.5×10^-5 g/ml) produced a slurr or step in the rising phase of the AP and gradual decrease in the AP-height together with negative inotropic effects, resulting finally complete conduction block and disappearances of the twitch tension in the LSVC as well as the LA.
4. The resting tension (tone) of the LSVC pretreated by Prop.(1.5-8.3×10^-6 g/ml) was markedly elevated by the application of Epin. and Norep.(3.3×10^-6 g/ml), but not by Isop.(1.3×10^-6 g/ml). All of Epin., Norep. and Isop. did not affect at all the resting tension of the IVC as well as the LA, even though pretreated equally by Prop. These results were discussed in relation to adrenergic alpha- and beta-receptors present in the tissue.
5. The application of Ach.(1.7×10^-5g/ml) induced the marked shortening of AP-duration and the drastic decrease in contraction-strength in the LSVC, and the succeeding addition of atropine (8×10^-7 g/ml) produced the supernormal contractions with a prolonged AP-duration. In the next application done after 20 minutes washout of the preparation, Ach. displayed directly the positive inotropic action. These diverse actions of Ach. were essentially similar to those observed in the LA.
6. Ouabain (2.5×10^-7 g/ml) increased the twitch tension of the almost all strips (90%) of the LA; but only 40% of the LSVC. On the other hand, no significant change was observed in the APs of both the LA and LSVC. This result may imply that the striated muscle component contained in the LSVC is not the same to the atrial muscle in the contractility to ouabain.
7. Finally, physiological significance of spontaneous rhythmic contractions (twitch tension) and sustained contraction (resting tension or tone) of the superior venae cavae near the heart was briefly speculated from the hemodynamic point of view.

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The sequence of spread of sinus node impulse to the venae cavae and the mechanisms of delay at the sinocaval junctional areas were studied with the microelectrode methods.
The impulse from the pacemaker located in the sinus node spreads slowly in the nodal tissues (1-10cm/sec) and excites the crista terminalis. Spread is rapid in the crista (50-120cm/sec). Then the impulse spreads from theupper and lower ends of the crista through the sinocaval junctional areas (SC areas) to the right and left superior venae cavae. Conduction velocity is decreased in the SC areas (10-25cm/sec) and again increased in the superior venae cavae (40-80cm/sec). In the inferior vena cava, the conduction of impulse is always completely blocked in the vicinty of the ostium.
The features of superior vena caval action potentials are closely similar to those of cardiac action potentials, showing the constant diastolic level, the rapid upstroke, the high amplitude, the clear plateau and the rapid conduction.
The fibers in the SC areas apparently show a transitional stage from the nodal fibers to the superior vena caval fibers. The action potentials of the SC areas are intermediate in the amplitude and rate of rise between those of sinus nodal and superior vena caval action potentials, and often reveal a step on the upstroke. The activation of right atrium at high rate produced a delay and block localized to the SC areas. The action potentials of the SC areas show three different types of changes associated with the increased atrial rate: I) the decrease in the amplitude and rate of rise, II) the separation into two discrete spikes and III) the widening of the step-like prepotential.
Several evidences were presented which suggest that the SC areas are the latent pacemakers.

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A single in jection of 50 I. U. PMS on day 28 produced ovulation on day 31. Systemic anesthetization by Nembutal on days 28 and 29 did not delay PMS induced ovulation, however, administration of Nembutal at 30 days of age, the day prior to PMS induced ovulation, did delay ovulation. Direct anesthetization by Nembutal of the preoptic area and the lateral septum on day 29 delayed the induction of precocious ovulation by PMS whereas injection into the mammillary body, basal part of the amygdala complex, or frontal cortex had no apparent effect. Also, a direct injection of Nembutal into the preoptic area before or during the critical period (2 to 4: 00 P. M.) was successful in delaying ovulation. However, if injection was made after the critical period the animal ovulated on schedule.
No ovulation after PMS administration in hypophysectomized rats was found, however, a significant uterine weight increase was observed. In rats with prior intrasplenic ovarian grafts no significant histological differences were observed between ovaries of rats treated with PMS and those not treated.
In rats given PMS and injected with metopirone twice daily for three days, ovulation was delayed. In those animals adrenalectomized and pre-treated with PMS, and given metopirone, ovulation was also delayed. However, adrenalectomized rats not injected with metopirone ovulated at the normal day for PMS induced ovulation. Although anesthetizing with Nembutal systemically on the day prior to PMS induced ovulation blocked this ovulation, an injection of metopirone did not.

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1. The nature and course of postnatal development of reflex deglutition were investigated by means of the single fiber recordings from the motor fibers of hypoglossal, accessory and phrenic nerves in unanesthetized, midcollicularly decerebrate cats and kittens of various postnatal periods.
2. The motor fibers of kitten hypoglossal nerve showed a great deal of variety of patterns of discharge during swallowing depending on the differences of the nerve fiber, the squirt of water into the oropharynx, the type of mechanical stimulation and the ventilatory state of the animal. The burst discharge was also produced in the nerve fiber innervating the muscles having no direct participation in the act of swallowing.
3. Gallamine-induced motoparalysis modified profoundly the pattern of the motor nerve fiber discharges both during swallowing and during electrical stimulation of the superior laryngeal nerve in the kitten.
4. The hypoglossal motor fibers which revealed the “swallowing discharge” in normal conditions produced the respiratory volleys when the animal was asphyxiated, whereas the phrenic motor fibers discharging rhythmically in phase with respiration produced the “swallowing discharge” (a complete silence in a few fibers) when a small amount of water was squirted into the oropharynx or the superior laryngeal nerve was stimulated electrically by repetitive pulses.
5. The response features of the motor nerve fibers of kitten hypoglossal nerve during swallowing gradually approached to those of the adult cats with the lapse of time in approximately 3 months postnatally.

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It was shown that the increased susceptibility to insulin after adrenalectomy in rabbits was mainly due to the absence of epinephrine secretion. Protective effect of glucocorticoids against insulin convulsion, when observed, was due to their hyperglycemic effect. They did not show any appreciable effects upon the susceptibility of central nervous system to hypoglycemia.
The degree of epinephrine secretion after insulin seemed to be determined rather by emotional reactivity than the dose of insulin given. The marked generalized sympathetic activation in insulin convulsion did not enhance epinephrine secretion. Thus the concept of “sympathetico-adrenomedullary system” could not be appreciated here.

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1. In cats carrying electrodes chronically implanted in the optic chiasm, some properties of spontaneous optic tract discharges (SOTD) were studied during natural sleep and under Nembutal anesthesia. In addition to a direct measurement of the absolute strength of the SOTD, discharges which had higher amplitudes than a certain level were (sampled electronically sampled SOTD) and their rate was counted.
2. Nembutal suppressed the SOTD below the level maintained during natural sleep.
3. Effects of steady retinal illumination upon the SOTD were examined. The finding of previous workers was confirmed that under a nembutalized condition the SOTD was mainly suppressed by retinal illumination. On the other hand it was revealed that retinal illumination caused a more or less increase of the SOTD in non-anesthetized, sleeping cats.
4. The SOTD was often found to diminish when the animals entered from light sleep to deep one.
5. The SOTD usually fluctuated greatly during a maintenance of deep sleep. This fluctuation of the SOTD was found difficult to be correlated to fluctuation of other biological activities such as the systemic blood pressure, the heart rate and the phasic body movements characteristics of deep sleep.
6. Spontaneous synchronization of the SOTD at 1-4 c/s (pulsing) was seen to occur when the once decreased SOTD was progressively attaining its original strength. This occurred usually in the transient phase between light sleep and deep one. It could also be seen during maintained sleep, either of light type or deep one, after the SOTD suffered temporarily a great reduction.
7. Recording the antidromic OT fiber responses under various strengths of the SOTD in different types of sleep, it was found that the antidromic responsiveness of the OT fiber terminals is determined according to the types of sleep, almost independently of the strength of the background SOTD.

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