Traumatic cerebral aneurysm associated with widening skull fracture. Report of two infancy cases

Two cases of traumatic cerebral aneurysm associated with widening skull fracture are reported. Cases of traumatic aneurysms in infants are particularly rare, and there have been no reported cases associated with widening skull fracture.

[Studies on the physical dependence liability of chlorphenesin carbamate (author's transl)]

Physical dependence liability of chlorphenesin carbamate (CPC) was studied in parallel with phenobarbital-Na (PB). Beagle dogs were used and the overall duration of the experiment was 85 days, i.e. the first dosing period was 42 dyas (6 weeks) in which drugs were repeatedly administered orally once daily, followed by a withdrawal period (7 days), the second dosing period was continued from the 50th-78th day in which the form and schedule of drug administration was as in the first dosing period. The last 79th to 85th days were used for substitution experiments. In both dosing periods, PB but not CPC showed signs of tolerance formation. Severe withdrawal syndrome was observed in PB administered dogs whereas there were no changes of behavior observed in CPC-dogs by withdrawal and substitution procedures, respectively. CPC apparently does not have a physical dependence liability.

[A pharmacological study of chlorphenesin carbamate. Tolerance to chlorphenesin carbamate (author's transl)]

Tolerance to chlorphenesin carbamate (CPC) was investigated from the viewpoints of action of CPC, serum free CPC concentration, the activity of UDP-glucuronyltransferase and the content of cytochrome P-450. CPC was administered once daily for 7 or 14 days. In mice, the hypnotic action of hexobarbital injected 24 hours after the last administration of CPC and the motor incoordinating action of CPC significantly decreased on the 7th day, but slightly recovered on the 14th day. Serum free CPC concentration also decreased on the 7th day, but recovered on the 14th day. A significant relationship between the motor incoordinating action of CPC and serum free CPC concentration was observed. Therefore, the recovery of CPC effect on the 14th day was considered to be due to the recovery from the induction of drug-metabolizing enzymes. On the other hand, in rats, the weekly alteration of the motor incoordinating action of CPC was similar to that observed in mice. Serum free CPC concentration on the 7th and 14th days was lower than that on the 1st day, and enzyme induction was observed during CPC administration. Notwithstanding the low level of serum free CPC concentration, the recovery of CPC effect was observed on the 14th day and such was considered to be due to habituation to the rotarod. In mice and rats, it was demonstrated that the intensity of CPC effect was dependent on serum free CPC concentration to the extent that enzyme induction played an important role in the development of tolerance. From these results, the tolerance to CPC is attributed to induction of drug-metabolizing enzymes in liver microsomes.

[Distribution of lithium and its effects on electrolyte and norepinephrine metabolism in discrete areas of the rat brain]

Lithium carbonate (Li2CO3) or lithium chloride (LiCl) was administered to rats, and distribution in discrete areas of the brain as well as the effects on electrolytes in the urine, blood and whole brain were investigated. Further, the effects of Li with or without methamphetamine on electrolytes and norepinephrine (NE) metabolism in discrete areas of rat brain were examined. After a single administration of Li2CO3 (2.7 mEq/kg p.o.), the Li concentration in all regions of the brain except the hypothalamus reached the maximum level at 12 hr and decreased gradually. A relatively high concentration was observed in the hypothalamus, a short time after the administration. After repeated administration of Li2Co3 (2.7 mEq/kg/day for 5 or days p.o.), the Li concentration did not increase in any region of the brain in comparison with after a single administration and there were no marked changes in the balance of electrolytes in the plasma and brain despite significant changes in the urinary electrolytes and urine volume. Acute administration of LiCl (2.4 mEq/kg and 1.2 mEq/kgx2 for 2 hr i.p.) did not affect the levels of NE and its metabolites in any region of the brain. Subacute administration of LiCl (2.5mEq/kg X 2/day for 4.5 days i.p.) concomitant with methamphetamine increased the deaminated metabolites of NE in the hypothalamus and hippocampus, whereas no influence was observed on the concentrations of sodium and potassium in any region of the brain. From these results, it is suggested that the hypothalamus is one area where Li exerts its action.

[Pharmacokinetics and general pharmacological actions of lithium salts administered singly or repeatedly]

Absorption, distribution and excretion after oral administration of lithium carbonate (Li2CO3) and/or lithium chloride (LiCl) were studied in Wistar rats and beagle dogs. The maximum level of concentration in the blood was seen within 4 hr after administration of Li2CO3, and a greater part of the orally dosed Li2CO3 was excreted into the urine. The blood and urine Li levels after the administration of LiCl were similar to those seen with Li2CO3. In dogs, Li2CO3 was more slowly excreted into the urine than it was in rats. Li was selectively incorporated into the thyroid and pituitary a short time after administration, and was not detected in any organ 7 days after cessation of repeated dosing for 19 days. The movement of Li into the brain was slow and relatively low levels were achieved after a single administration, but high and constant levels were shown after repeated administration. Effects of Li salts on behavior of ddy mice with repeated administration were investigated. The spontaneous motor activity was suppressed with Li2CO3 more strongly than with LiCl. The high dose of Li2CO3 suppressed not only the stimulating actions of methamphetamine and cocaine, but the ptotic and hypothermic action of reserpine. From these results, it is concluded that the repeated administration of Li salts reveals higher levels of Li ion in the brain than does a single administration, and also more responsive action on the central nervous system.

[Effect of dopamine on perfusion pressure in rat peripheral blood vessels]

Rat mesenteric and hind limb arteries were perfused with the rat's own blood under constant perfusion rate, in situ. The effect of dopamine (DA) administered intraarterially was investigated and compared with effects of norepinephrine (NE), tyramine (Tyr), and phenylephrine (PHE). The magnitude of the vasoconstrictive maximum response of both vasculatures to NE and PHE was larger than those to DA and Tyr, and those to DA were larger than those to Tyr in hind limb, but those to Tyr were more potent than those to DA in the mesenteric artery. The vasoconstriction evoked by celiac ganglionic stimulation was much the same to that evoked by NE and PHE. Under cocaine infusion, the rise in perfusion pressure of both vasculatures evoked by NE and PHE. Under cocaine infusion, the rise in perfusion pressure of both vasculatures evoked by NE was slight, but the duration was markedly potentiated. However, the effect of Tyr was suppressed and that of DA was not changed. In rats on alpha-methyl-rho-tyrosine, the responses of both vasculatures to Tyr were reduced and those to NE and DA were not changed. In the reserpinized rat, the effect of NE was not changed and that of Tyr was reduced, while that of D was more evident in both vasculatures. After phenoxybenzamine treatment, vasoconstrictive effect of DA was reversed in mesenteric and reduced in hind limb artery. Vasodilating effect of DA after phenoxybenzamine, was not changed by treatment with propranolol, atropine, and diphenhydramine but was reduced with reserpine and abolished with haloperidol. These results suggest that the vasoconstrictive effect of DA depends partly on indirect sympathomimetic action, and after phenoxybenzamine, DA acts by vasodilating the DA receptor. Potentiation with reserpine may depend on a post-synaptic mechanism and increase in dopamine-beta-hydroxylase activity.