Possible functioning of active ion transport mechanism in the mucous epithelial cells of newt stomach at low temperature

The membrane potential of mucous epithelial cells of isolated newt stomach was -23 mV on the average at 7 degrees C. The potential decreased when the temperature was lowered further, the normal external solution was replaced with K+-free solution, or ouabain or DNP was applied. The decreased membrane potential level of the cells in K+-free solution was not changed any more by adding ouabain to the solution. The membrane potential increased transiently beyond the control level when the stomach was returned to the normal solution after being exposed to isotonic NaCl solution with EGTA. The transient potential increase was blocked by ouabain. These results suggest that, even at such a low temperature as 7 degrees C, the active ion transport mechanism(s) of mucous epithelial cells in the newt stomach is still capable of functioning to some extent.

[Gross and light microscopic observations of the pudendal nerve of the guinea pig (author's transl)]

Using thirty six adult guinea pigs, the course and distribution of the pudendal nerve was observed macroscopically and then the constitution of the myelinated nerve fibers in these branches was studied with the fan-wise split preparation method (Fukuyama) and the cross sections embeded in paraffin wax. The main findings are summarized as follows: 1) The pudendal plexus in the guinea pig is formed most frequently by a bigeminal nerve which arises from the ventral ramus of the second sacral nerve at an average rate of 55.0% and the pudendal nerve is so independent from the sciatic nerve that the most part of the bigeminal nerve runs into the pudendal nerve. 2) The perineal nerve of the guinea pig arises most frequently with four roots (43.3%). The myelinated fiber constitution of this nerve is as follows: The small-sized fibers occupy 49.8%, the medium--sized 21.9%, the large--sized 15.1%, the maximum--sized 13.1% on an average, and the nerve fiber diameters observed in the cross section shows a bimodality in their distribution, of which the fibers in the higher peak are 1 mu to 2 mu and in the lower peak 5 mu to 8 mu. 3) The dorsal nerve of the penis or clitoris of the guinea pig arises most frequently with one root from the originating roots of the perineal nerve. The relationship between the sciatic and dorsal nerve appears to be scanty. The myelinated fibers of this nerve comprise 50.8% of small--sized, 28.4% of medium--sized, 14.7% of large--sized and 6.2% of maximum--sized fibers on an average. The fiber sized histograms constructed in the cross section shows a unimodality laying at 1 mu to 3 mu and the dorsal nerve of the clitoris contains more medium fibers 3 mu to 6 mu than the perineal nerve. From these results, it seems clear that the genital corpuscles are supplied by these medium fibers. 4) The inferior rectal nerve of the guinea pig arises from the perineal nerve in all cases, however, it is very slender. 5) The branch to the Obturator internus arises from the originating root or main trunck of the perineal nerve (51.7%). The myelinated fiber constitution of this branch is as follows: The maximum--sized fibers occupy 67.6%, the large--sized 16.2%, the small--sized 9.5% and the medium sized 6.8%. On the other hand, the fiber diameters observed in the transverse section are distributed around three peaks lying at 1 mu, 8 mu to 9 mu and 12 mu to 13 mu. 6) The branch to the accessory head of the Semitendinosus arises from the pudendal nerve at an average rate of 91.7%, of which this branch arises most frequently with one root from the originating root of the perineal nerve. The myelinated fiber constitution is as follows: The maximum--sized fibers 50.0%, the large--sized 23.9%, the small--sized 15.9% and the medium--sized 10.2% on an average. The histogram shows that myelinated fibers in this muscular branch consist of two groups of 1 mu to 2 mu and 12 mu to 14 mu...

Inhibitory effect of large doses of propylthiouracil and methimazole on an increase of thyroid radioiodine release in response to thyrotropin

Thyroidal radioiodine release increased shortly after a single injection of small doses of PTU, while moderate doses of MMI produced a similar increase of thyroidal radioiodine release with a latency of 7-9 hr. Large doses of PTU and MMI failed to augment thyroidal radioiodine release for at least 29 to 34 hr after the initial administration of goitrogens, although plasma TSH increased significantly because of goitrogen administration. An increase of thyroid hormone release in response to exogenous TSH was depressed by PTU and MMI in rats and mice treated with T4. Since this depression of TSH action only continued for a short period in spite of continuous administration of goitrogens, and since final thyroidal radioiodine release rate was similar to that produced by small doses of PTU, the effects mentioned were not simply due to general toxic action of goitrogens. It is suggested that large doses of PTU and MMI not only block thyroid hormone synthesis but also interfere with the action of TSH on thyroid hormone secretion.

[A case of the A. Vertebralis sinistra direct arising from the arcus aorta (author's transl)]

A case of the left vertebral artery direct arising from the Arcus aorta, falling under C-type in ADACHI (1928), was encountered among the corpses dissected for practice in Hokkaido University, school of medicine. The Arcus aorta has four branches; Truncus brachiocephalicus, A. carotis communis sinistra, A. vertebralis sinistra, and A. subclavia sinistra. The A.vertebralis sinistra has passed through at first into Foramen transvwrsarium of the vertebra cervicales quintus (C5). The length of this artery between the origin of the Arcus aorta and the fifth cervicales was 120 mm. The other measurements of arteries were shown in table 1.

[Studies on the pudendal nerve. Part 4. A macroscopical observation of the branches of the pudendal plexus in dogs and cats (author's transl)]

The pudendal plexus and its branches of 20 dogs and 20 cats have been observed macroscopicaly. The main findings are summarized as follows: 1) The pudendal plexus in dogs is formed most frequently by the ventral rami of the first, second and third sacral nerves. 2) The bigeminal nerve of dogs and cats is formed respectively by the union of the ventral rami mentioned above. 3) The perineal nerve in dogs arises with one root from the bigeminal nerve and that of cats two roots, of which the main root arises from the points where the bigeminal nerve joins the asciatic nerve and the accessory one from the bigeminal nerve. 4) In dogs and cats the dorsal nerve of the penis or clitoris arises from the main trunk of the perineal nerve (Fig. 5, type IB) at an average rate of 57.5%. 5) In the dogs and cats, the inferior rectal nerve consists of two divisions; a division had the branches which are derived the perineal nerve to supply the skin around the anus and the other branches which arises from the muscular branch of the dorsal nerve of the penis or clitoris to supply the Sphincter ani externus. 6) The muscular branch of dogs and cats which is analogous to that of the perineal nerve in man, arises from the dorsal nerve of the penis or clitoris. 7) In dogs and cats the muscular branch to the Obturator internus is derived from the dorsal nerve of penis or clitoris. 8) The pelvic splanchnic nerve of dogs originates from the ventral rami of the first, second and third sacral nerves and that of cats from the ventral rami of the first and second sacral nerves. 9) In the posterior femoral cutaneous nerve in dogs, as well as in rats and rabbits, the lateral deviation of the origin from the sciatic to the perineal nerve is observed.

Effect of butyldiiodohydroxybenzoate on pituitary-thyroid interplay

The effect of BHDB, an analogue of thyroxine, on the pituitary-thyroid system was studied in the rat. BHDB produced low plasma T4 and T3 concentrations similar to those produced by methimazole, but failed to elevate plasma TSH and to produce goiter because of displacement of T4 from the binding protein. Low plasma thyroid hormone concentrations were due to an increase of fecal loss of thyroid hormones. By releasing excess iodide, BHDB blocked the development of goiter produced by methimazole.

Intercellular communication and tissue growth. I. Cancerous growth

Intercellular communication was examined with intracellular electrical techniques in primary and transplanted rat liver cancers. Normal liver cells communicate rather freely with each other through permeable junctional membranes. Cancer liver cells show no communication at all; their surface membrane is a strong barrier to diffusion all around the cell. Cancer cells induce alterations in membrane permeability in normal liver cells; communication among the latter is markedly reduced when cancer cells grow near them.

Intercellular Communication: Renal, Urinary Bladder, Sensory, and Salivary Gland Cells

In four epithelial cell systems (salivary gland, renal, urinary bladder, and sensory cells) cells are interconnected as far as much of their ion content is concerned. In the salivary gland and renal epithelia, all cells of the epithelium are interconnected; and communication between a given cell and any of its nearest neighbors is equally good. In the bladder and sensory epithelia, communication appears to be more restricted, manifesting itself in chains of connected cells in the former, and in small groups of connected cells in the latter. The permeability of the cell membrane at the junction between connected cells is several orders of magnitude greater than it is at the cell surface bordering the exterior of the cells. Each connected cell ensemble functions as a system with a fairly continuous cytoplasmic core bounded by a diffusion barrier which is continuous along the entire outer surface of the system. As a result, ions move rather freely from cell to cell, but not from cell interior to exterior. Intercellular communication in at least three epithelia is associated with the presence of certain close-junctional membrane complexes.