Pharmacokinetic and behavioural profile of THC, CBD, and THC+CBD combination after pulmonary, oral, and subcutaneous administration in rats and confirmation of conversion in vivo of CBD to THC

Metabolic and behavioural effects of, and interactions between Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD) are influenced by dose and administration route. Therefore we investigated, in Wistar rats, effects of pulmonary, oral and subcutaneous (sc.) THC, CBD and THC+CBD. Concentrations of THC, its metabolites 11-OH-THC and THC-COOH, and CBD in serum and brain were determined over 24h, locomotor activity (open field) and sensorimotor gating (prepulse inhibition, PPI) were also evaluated. In line with recent knowledge we expected metabolic and behavioural interactions between THC and CBD. While cannabinoid serum and brain levels rapidly peaked and diminished after pulmonary administration, sc. and oral administration produced long-lasting levels of cannabinoids with oral reaching the highest brain levels. Except pulmonary administration, CBD inhibited THC metabolism resulting in higher serum/brain levels of THC. Importantly, following sc. and oral CBD alone treatments, THC was also detected in serum and brain. S.c. cannabinoids caused hypolocomotion, oral treatments containing THC almost complete immobility. In contrast, oral CBD produced mild hyperlocomotion. CBD disrupted, and THC tended to disrupt PPI, however their combination did not. In conclusion, oral administration yielded the most pronounced behavioural effects which corresponded to the highest brain levels of cannabinoids. Even though CBD potently inhibited THC metabolism after oral and sc. administration, unexpectedly it had minimal impact on THC-induced behaviour. Of central importance was the novel finding that THC can be detected in serum and brain after administration of CBD alone which, if confirmed in humans and given the increasing medical use of CBD-only products, might have important legal and forensic ramifications.

[Significance of determination of intra-acrosomal proteins and sperm antibodies in human reproduction]

OBJECTIVE

Comparison of the positive intra-acrosomal proteins and spermagglutinating antibodies in human semen samples from various groups of patients.

DESIGN

Prospective study.

SETTING

Department of Gynecology and Obstetrics and Faculty Hospital, Charles University, Pilsen, Institute of Molecular Genetics, Czech Academy of Science, Prague.

METHODS

Monoclonal antibodies Hs-8 and Hs-14 (prepared in the Institute of Molecular Genetics, Prague) were used for detection of intra-acrosomal sperm proteins. Microscopic immunofluorescent methods detected the incidence, the character and the percentage of the spermatozoa specified by above-mentioned monoclonal antibodies. Direct mixed anti-immunoglobulin reactions test (MAR-test) for IgG, IgM, IgA, IgE was used for detection of spermagglutinating antibody. We examined 315 infertile patients from Special Consultation for Immunology of Reproduction and from the IVF programme, and sperm healthy donors (January 2002-March 2003).

RESULTS

Native donor's sperm cells had excellent positive intra-acrosomal proteins stained with monoclonal antibodies Hs8 and Hs14 and after thawing as well as. No spermagglutinating antibodies were found. In the group with normal sperm count and light microscopic morphology we found the presence of seminal spermagglutinating antibodies in 11% (IgG), in 14.5% (IgA), in 3.6% (IgM), in 5.2% (IgE). Significant positivity of intra-acrosomal protein stained with Hs8 monoclonal antibody was reached in 68.4%, and with Hs14 monoclonal antibody in even 81.3% of men. On the other hand, in oligoasthenospermatic patients we found significant increasing of spermagglutinating antibodies (for IgG 40.5%, for IgA 28.6%, for IgM 9.5%, for IgE 11.9%). Dominant good staining of intra-acrosomal proteins were seen only in 15.5% of men (for Hs8) and in 20.2% (for Hs14).

CONCLUSION

The quantitative detection of intra-acrosomal sperm proteins and spermagglutinating antibodies are used as important properties of human semen and serve for evaluation of acrosomal state, and male fertility together.

[Antizonal antibodies in ovulatory cervical mucus and in serum of patients with fertility disorders]

OBJECTIVE

Detection of antizonal antibodies (aZPs) in cervical ovulatory mucus and in serum in patients with fertility failure.

DESIGN

Retrospective study.

SETTING

Department of Gynaecology and Obstetrics, Medical Faculty of Charles University, and Faculty Hospital, Plzen.

METHODS

Detection of aZPs (passive hemagglutination test) in cervical ovulatory mucus (OM) and in serum from 105 patients with reproductive failure and in 25 fertile healthy women (control group).

RESULTS

Positive levels of aZP in OM were found in 79 (75.2%) patients, in 56 of them aZP were observed in OM and in serum together, only ovulatory aZPs in 23 (21.9%), and only serum aZPs in 18 (17.1%) were found. aZPs predominate in 47 patients (of 48 women) with more than two in vitro fertilization processes, in thirty of them aZPs in serum and in OM together were observed. On the other hand, repeated spontaneous miscarriage and obesity have no connection with detection of aZPs in our patients. CONCLUSION. The increased levels of serum and OM aZPs are very often seen in patients after repeated unsuccessful IVF. This very important result in reproductive immunology means to go on the micromanipulation technics combined with immunosuppression in the next planned IVF procedure.

Gestational progesterone suppresses embryotoxic action of the complement system to chick embryo

OBJECTIVE

In this paper the relation between progesterone levels and embryotoxic effect of serum complement was studied.

DESIGN

The aim of this study was to validate hypothesis that progesterone is strong inhibitor of complement embryotoxic action.

SETTING

We used chick embryo like an experimental model for evidence of our hypothesis. We treated chick embryos by sera acquired from healthy pregnant woman with physiologically elevated levels of progesterone and normal complement activity. We investigated embryotoxicity of these sera.

RESULT

We noticed a significant decrease of sera embryotoxicity inversely related to serum levels of progesterone. The main finding: The embryotoxicity of sera is reversally dependent on progesterone level.

CONCLUSIONS

These findings bring a new knowledge to the role of progesterone and complement system mainly in initial stages of pregnancy and in some cases of spontaneous abortions.