In loco and systematic alteration in vitamin A content during tail regeneration in the gekkonid lizard, Hemidactylus,flaviviridis

A quantitative evaluation was made of the levels of vitamin A in the liver, kidney and tail regenerate during tail regeneration in H. flaviviridis. Vitamin A in the liver increased on the first three days and decreased on the 5th day post-autotomy; a second increase was noted on the 7th day. Thereafter a subnormal level was noted on the 10th, 15th and 25th days. Vitamin A levels in the tail remained raised throughout regeneration except on the 7th and 60th days when the levels were in the normal (pre-autotomy) range. Kidney vitamin A content showed a steep increase on the 10th day while at other periods it remained in the normal range. The depletion in hepatic vitamin A content corresponded with high vitamin content in the regenerate, indicating the mobilization of this vitamin to the site of regeneration. The decreased level during dedifferentiation indicates greater utilisation of this vitamin. Supra normal levels of vitamin A in the regenerate during the blastemic and differentiation phases suggest an intimate association of this vitamin with the many events characteristic of these phases of regeneration.

Alteration of Platelet Cyclic AMP (cAMP) by Ethanol

Studies of cAMP in human platelets exposed to ethanol were done to assess one possible mechanism for ethanol-related platelet dysfunction. Ingestion of ethanol by 3 subjects produced blood ethanol levels from 65-76 mM. Thrombocytopenia occurred in 1 subject and impaired platelet function occurred in all. Platelet cAMP decreased 36,51, and 59% below control levels. Infusion of ethanol to 2 normals produced blood ethanol levels of 43 mM and decreased platelet cAMP by 15% and 22%. Incubation of normal platelets with 86 mM ethanol in vitro decreased cAMP from 13.8 ± 2.9 (1 SD) to 9.4 ± 3.5 (p<0.02). By contrast, ethanol did not impair the increase in cAMP that occurred with 1.3 μM PGE1. Further, ethanol enhanced the increase in cAMP produced by 2.0 mM papaverine (Pap) by 160-220% and that produced by Pap + PGE1 by 58%. Dopamine, 0.1 mM, caused a 23% decrease in the basal level of cAMP, a 31% decrease below the subnormal level of cAMP seen with ethanol alone, and a 41% reduction in the increased level of cAMP produced by Pap + ethanol. The effect of ethanol on platelet cAMP metabolism is complex. Ethanol reduces basal levels of cAMP, does not decrease elevated levels that result from PGE1 stimulation of adenylate cyclase, and augments the inhibitory effect of Pap on platelet phosphodiesterase (PDE). Despite causing a decrease in basal cAMP levels, ethanol may impair platelet function by potentiating the effect of agents or other conditions which increase cAMP. The effect of ethanol on Pap-stimulated PDE activity may be blocked by dopamine, a neuropharmacologic agent that is actively accumulated by platelets.

Socio-Economic Status and Post-Trauma Intelligence in Children with Severe Head Injuries

Study of 46 severely head-injured children suggests that the degree of intellectual recovery post-trauma is best predicted by the age at injury. These younger children generally fared less well than older children. However, socio-economic affiliation also was a determining factor. The majority of younger children were from the lower socio-economic class and proportionately more younger than older children of lower-class affiliation functioned at the subnormal level. In contrast, for the middle-class group proportionally as many younger as older children functioned at the subnormal level.

THE EFFECT OF ANAESTHESIA ON MILK YIELD AND MAINTENANCE OF LACTATION IN THE GOAT AND RAT

SUMMARY The effect of anaesthesia on lactation was studied in the lactating goat and the lactating rat. Cyclopropane was used in the goat. All goats were milked once daily in the morning. The experimental and the control periods started on Monday and ended on Saturday; the control period was usually followed immediately by the experimental period. Average milk yields in eight experimental periods in three goats ranged from 91·4 to 108·3%, with a mean of 101·4±1·84% (s.e.) of those in the corresponding control periods. The increase in intramammary pressure, which occurred 30–40 sec. after the start of milking of the contralateral teat in the normal lactating goat, was not observed during milking under anaesthesia. Lactating rats were anaesthetized with sodium pentobarbitone. Six or eight pups were placed with the mother to suckle the teat for 2 hr. in the morning. This suckling regime was continued for 5 days. No increase in the body weight of litters was obtained when the litter suckled under anaesthesia. When oxytocin was injected into the anaesthetized mother, a gain in litter weight was observed during the experimental period, although it was smaller than in the controls. In conclusion, a species specificity in the importance of the milk ejection response for the removal of milk has been demonstrated. The fact that milk secretion continued normally in the goat milked under the anaesthesia suggests that the secretion of the pituitary hormones concerned with the maintenance of milk secretion continues in the absence of the milking stimulus. In the rat, although milk secretion was maintained at a subnormal level by oxytocin replacement under anaesthesia, it was not possible to draw a final conclusion as to whether the suckling stimulus is dispensable for the maintenance of milk secretion.

Blockage of milk removal in the cat by periventricular diencephalic lesions

Electrolytic lesions were placed in several structures of the CNS in lactating cats. Lesions in the periventricular region of the caudal hypothalamus resulted in stoppage of established lactation. This effect was due to failure of milk removal. Oxytocin when administered from the 1st postoperative day permitted lactation to continue, though at a subnormal level. The results suggest that through the periventricular diencephalic region course afferent fibers to the neurohypophysis which are involved in the oxytocin reflex release induced by suckling.

Factors causing alterations of the level of inorganic phosphorus in the blood of zebu cattle

Studies have been made on calcium and inorganic phosphorus in pasture grass and their relationship to blood levels in Zebu cattle.Excitement, adrenaline injections and fatigue were investigated as possible causes of variations in the inorganic-phosphorus levels of the blood of Zebu cattle.Sudden rainfall appeared to cause alterations in the inorganic phosphorus levels of blood. This hypothesis, when tested on two separate batches of cattle on two occasions, showed that there was a highly significant relationship between water intake and the level of inorganic phosphorus of Zebu cattle blood.Water starvation caused a steady increase in the level of inorganic phosphorus and when water was available for the cattle to drink the inorganic phosphorus level fell rapidly to a subnormal level before returning to normal. These results are discussed in the light of the available literature.

Seromucoid in Hepatobiliary Disease

Seromucoid was determined in 165 patients with jaundice or hepato. megaly, or both. Subnormal seromucoid concentrations were found in 39 per cent of 44 cases of viral hepatitis and in 15 per cent of 41 cases of alcoholic cirrhosis. This incidence increased to 50 and 43 per cent, respectively, when patients with complicating extrahepatic disease processes were excluded. No subnormal values were encountered in 55 cases of benign and malignant biliary obstruction which, however, yielded about 80 per cent of elevated values. The empirical data point to the lower limit of the normal seromucoid range as providing a useful dividing line between obstructive and parenchymal jaundice: the finding of a subnormal level is strongly indicative of the latter. Normal or elevated levels may only occasionally be expected to make a decisive diagnostic contribution. A more definitive evaluation of the clinical utility of this type of test must await improvements in analytic standardization, based on a more detailed knowledge of the chemical and physiologic identity of the compound than is available at present.

The effects of morphine, diacetylmorphine and some related alkaloids upon the alimentary tract: Part III. Caecum and colon

1. The effects of morphine, heroin, codeine, dilaudid, dicodid and eukadol upon the caecum and colon are described.2. Small quantities of morphine produce a rapid increase in tone and amplitude of movements lasting many hours. Large doses result in a spastic contraction of the intestine with diminution of peristaltic movements.3. The effects of heroin closely resemble those of morphine; it usually produces a greater increase in tone than morphine but the movements are not so great. Heroin is about 30% more active than morphine.4. Codeine appears to be the weakest member of the series. It causes a slight increase in tone and peristaltic movements which never last very long.5. Dilaudid produces effects which closely resemble those of morphine and heroin but it is approximately 7.5 times more potent than morphine. Intestinal tone is increased at first but may be subnormal at the 3 or 4 hr. stage. The maximum amplitude of peristaltic movements is seen at the 3 hr. stage.6. Dicodid increases the tone, and particularly the peristaltic movements. The effects upon the general tone are moderate, much less than those of morphine, heroin or dilaudid. The increase in the amplitude of the movements is, however, much greater than with any other of the drugs. It differs from the others in producing its effects only after a long latent interval of 1–2 hr.7. Eukadol increases the peristaltic movements in a marked way and is more active in this respect than either morphine or heroin, but is inferior to dicodid. Its effects upon tone are very transient and never very marked.8. The effects of all these drugs upon the tone and peristaltic movements are at once abolished by adrenalin or atropine. Except morphine and eukadol, these drugs failed to produce their effects when administered after full doses of atropine.9. The injection of hypophysin during the phase of increased muscular activity following the injection of these drugs, always causes an immediate abolition or diminution of the peristaltic movements and loss of tone to a subnormal level. There is however a rapid recovery from this state and approximately 5–10 min. later the movements are increased to an amplitude far in excess of that seen perior to the injection of hypophysin.

The effects of morphine, diacetylmorphine and some related alkaloids upon the alimentary tract: Part I. Stomach and pylorus

1. The effects of morphine and diacetylmorphine upon the stomach of the cat are variable. The greater number of experiments showed a decrease in tone which was accompanied by a decrease in the frequency and amplitude of movements. Some animals showed an increase in stomach tone accompained by three to five slowly moving contractions of great amplitude while no change were recorded in two cats.2. Codeine sometimes produced a slight increase in the amplitude of stomach movements with a diminished frequency, while at first the general tone is unaltered. Tone is later reduced slightly to a subnormal level. In other cases it causes a very slight increase in tone and amplitude of movements. These effects are short lived and very small when compared with those produced by morphine or heroin.3. The effects of dihydromorphinone (dilaudid) upon the stomach are far from constant. Most animals show an immediate relaxation of the stomach with a decrease in the amplitude of the movements. In a series of nine experiments, six showed relaxation of the stomach, two contraction, and in one no changes were recorded.4. The effects of dihydrocodeinone (dicodid) on the stomach resemble those of codeine. They consist of a small gradual increase in tone followed by a relaxation to a subnormal level.5. Dihydro-oxycodeinone (eukodol) produces effects which resemble those of dihydrocodeinone (dicodid).6. All these drugs produce constant effects upon the pyloric sphincter. They all produce an increase in the tone of the sphincter accompanied by an increase in the amplitude of the rhythmical movements. Dilaudid is approximately eight times more active than morphine, while diacetylmorphine is about one and a half times more potent than morphine. The effects of these three drugs last several hours.The effects of codeine, dicodid and eukodol show a great similarity. They are of short duration and very small when compared with morphine, heroin and dilaudid.