Undrugged rotational response in nigro-striatal system-lesioned rats is related to the previous early response to apomorphine when repeatedly administered

Development and time-course characteristics of undrugged rotational response weeks or months after repeated apomorphine administration in 6-hydroxydopamine-lesioned rats were explored. In one series of experiments, all groups received several drug doses two-three weeks post-lesion and remained undrugged at different intervals from the last drug injection. Weeks or months later, they were injected with saline in the same environment where they previously had received apomorphine. In this way we studied acquisition, time-course and extinction of the rotational response after saline. Furthermore, we related this undrugged response which does not fully develop until two weeks after treatment, and which previously had not been related to a specific parameter of the rotational response to the drug, to a critical point of the time-course response to the drug, i.e., the early rotational response in the first minute after injection. This early response is a learning phenomenon based on the environmental cues where drug has been repeatedly administered. Finally, we state the concept of pharmacological conditioning using this animal model of Parkinson's disease, in agreement with our own results and the previous results of Silverman and Ho (1981).

Antigenic enzymes of Schistosoma mansoni: possible use for immunodiagnosis

Different enzymes of Schistosoma mansoni are recognized by IgG antibodies present in the sera of infected human patients. The antigenicity of these enzymes suggests their possible use in immunodiagnostic assays that would take advantage of their activities.

Thromboelastographic assays of the clotting process in situations of obesity and caloric restriction

A study on blood clotting has been carried out in a number of obese individuals and compared to a group of non-obese persons, in order to assess if the former can be considered to be in "high risk" regarding the onset of a thromboembolic process. The technique of thromboelastography was chosen. The results point out that in obese people a series of alterations take place, both in the time of clot formation, which is enlarged, as in the organization of its nets, which appear strongly structured, favoured by the hyperfibrinogenemia and thrombocytosis detected in these subjects. Likewise, the effect of a hypocaloric diet on clotting in obese persons has been evaluated and compared with the former groups. Clotting in treated obese individuals is modified in the same way as in the untreated group when compared to the non-obese population; nevertheless, when both groups of obese people are compared, no significant difference is observed in the different parameters studied, even though constants determined in citrated whole blood are closer to normality in the subjects undergoing caloric restriction.

[Non-linear analysis of arterial pressure]

A macroscopic nonlinear mathematical model of simulation of the different mechanisms that participate at long, medium and short term in the arterial pressure regulation is described. In order to establish the availability and usefulness of this model two types of conditions were simulated. The first ones were compared to the results obtained in live experiments in dogs and the other ones were referred to the data from clinical research. This model makes possible both the qualitative and quantitative appreciation of the sequence of physiological events whenever a disturbance modifies the normal conditions in the control of the arterial pressure. This model is easy to handle in both clinical and experimental applications since it does not require the knowledge of computer handling for its operation.

[Effect of pineal indoles and testosterone on sex behavior]

The possible action of melatonin and 5-methoxytryptophol, two pineal indoles, upon castrated male rat sexual behaviour with three testosterone dose levels was studied. Both indoles reduced the number of mounts and intromissions. 5-Methoxytryptophol, in addition, decreased the number of ejaculations. The sexual actions of the pineal indoles are prevented by the administration of high testosterone dose levels (500 micrograms/day).

[Influence of posture changes on oncotic pressure and RHE proteinaemia (author's transl)]

Variations in proteinaemia levels in healthy man from posture changes or from physical exercise, as well as their chemical and physical consequences in plasma colloid-osmotic pressure, have been studied. Proteinaemia and oncotic pressure were measured in ten young males while lying flat, walking about, standing up motionless at attention and once again in a lying flat position. Proteinaemia and oncotic pressure increased on changing from a lying posture to orthostatism. The increase was much greater when the subjects were kept at rigid attention. Walking about did not produce any significant changes independently of the time factor. A significant correlation between changes in oncotic pressure and proteinaemia was always present. Changes in the oncotic pressure, however, were statistically more important.

Right ventriculography as a valid method for the diagnosis of tricuspid insufficiency

The value of right ventriculography in the diagnosis of tricuspid insufficiency (TI) is often questioned because of 1) the high incidence of premature ventricular contractions (PVCs) during injections and 2) interference of the catheter in the valve closure mechanism. In 168 patients a commercially available, not preshaped, balloon-tipped catheter was used for right ventriculography. To avoid the induction of PVCs, the catheter tip was placed in the middle third of the diafragmatic wall of the right ventricle, and the balloon was inflated, becoming trapped by the trabeculae. In this position the catheter's side holes should be located in the inflow chamber. To ensure this correct position, and therefore lack of ectopic beats during angiography, a saline test injection was performed previously in every case. With this technique the incidence of PVCs during ventriculography was only 7.7%. In all but one case, such beats were isolated. The 168 patients were divided into three groups according to their likelihood of experiencing tricuspid interference by the catheter: group 1 included 41 patients with a normal heart or with coronary artery disease. No one from this group had TI. Of group II, 28 patients with right ventricular pressure or volume overload or cardiomyopathy, only 2 had TI, both with a previous clinical diagnosis of regurgitation. Group III contained 99 patients with rheumatic heart disease. Thirty-five of them showed angiographic TI, and 24 of these had this diagnosis confirmed either clinically or at surgery. It is felt that this technique of right ventriculography, with its low incidence of PVCs and slight interference with tricuspid closure, is a valid method for the objective study of the tricuspid valve.