SHORT-TERM REGULATION OF LH AND FSH SECRETION IN CYCLIC WOMEN

1979 ◽  
Vol 90 (3) ◽  
pp. 394-402 ◽  
Author(s):  
A. Römmler ◽  
C. Viebahn ◽  
U. Schwartz ◽  
J. Hammerstein
Keyword(s):  
Dose Response ◽  
Elevated Serum ◽  
Serum Levels ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Group I ◽  
Before And After ◽  
17 Hydroxyprogesterone ◽  
Lh Rh ◽  
Lh Releasing Hormone

ABSTRACT The effects of two consecutive LH-RH injections at 120 min intervals with either a varying first or second LH-RH dose on pituitary gonadotrophin response were investigated in 15 eugonadal women to study pituitary secretory processes. Each volunteer underwent a total of 4 LH-RH double stimulation tests. In group I (n = 8) the first LH-RH dose of each of the 4 tests was fixed at 25 μg, whereas the second LH-RH dose consisted of either 6, 25, 100 or 400 μg. In group II (n= 7) the first LH-RH dose varied between 6 and 400 μg, while the second LH-RH dose was kept constant at 25 μg. Serum gonadotrophin and serum ovarian steroid levels were determined by radioimmunoassay before and after LH-RH administration. The volunteers in both groups served as their own controls. A linear log-dose response relationship was found between the various doses of LH-RH injected and the corresponding LH and FSH elevations elicited. However, the dose of the first LH-RH injection also significantly influenced the gonadotrophin reaction after the second LH-RH injection in a linear log-dose response relationship. Serum levels of oestradiol, 17-hydroxyprogesterone and progesterone significantly increased in response to the elevated serum gonadotrophin levels after LH-RH stimulation during the 4 h test period, but the rise did not correlate to the LH-RH dose used. The results indicate that LH-releasing hormone stimulates not only the release, but also the synthesis of LH and FSH in a dose-related manner. These findings are consistent with our previously reported concept that the magnitude of LH and FSH response to the first LH-RH injection reflects the "storage capacity", while the increase observed after the second LH-RH injection represents the "synthesis capacity" of the gonadotrophs.

Action of histamine on the rapidly adapting airway receptors in the dog

1989 ◽  
Vol 67 (12) ◽  
pp. 1499-1505 ◽  
Author(s):  
K. Ravi ◽  
K. K. Teo ◽  
C. T. Kappagoda
Keyword(s):  
Receptor Antagonist ◽  
Dose Response ◽  
Geometric Mean ◽  
Lymphatic Drainage ◽  
Threshold Dose ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Excitatory Effect ◽  
Before And After ◽  
The Right

The effects of histamine on the activity of rapidly adapting receptors (RAR) of the airways were investigated in anesthetized dogs. With bolus injections given into the right atrium, the threshold dose of histamine required for the excitation of RAR (n = 7) was 0.82 μg/kg (+1.33/−0.51, geometric mean). With increasing doses of histamine, a dose–response relationship was seen in the activity of RAR. Obstruction of the lymphatic drainage from the lungs reduced the threshold dose to histamine (i.e., shifted the dose–response curve to the left significantly). This change in the dose–response relationship was not accompanied by a corresponding change in the relationship of histamine dose to airway pressures recorded before and after lymphatic obstruction. Against a background of pulmonary venous congestion produced by partial obstruction of the mitral valve, subthreshold doses of histamine stimulated the RAR (n = 4). The excitatory effect of histamine on RAR was found to be abolished by the administration of the H1 receptor antagonist diphenhydramine but not by the H2 receptor antagonist cimetidine. Intravenous infusion of histamine (0.4 μg∙kg−1∙min−1) for a period of 10 min increased the RAR activity (n = 6) significantly without producing detectable changes in airway mechanics. The results indicate that contraction of the smooth muscle of the airways may not be a prerequisite for the excitation of RAR, especially at low doses. It is suggested that some of the effects of histamine on RAR are mediated by a local expansion of the extravascular fluid caused by an increase in the permeability of the bronchial vasculature.Key words: histamine, pulmonary congestion, vagal sensory receptors.

scholarly journals A Dose-Response Study in Man of the Metabolism of Enflurane Used as a Supplement

1977 ◽  
Vol 5 (3) ◽  
pp. 198-206 ◽  
Author(s):  
C. J. Lowry ◽  
J. H. Sharp ◽  
J. E. Shumacher ◽  
M. J. Cousins
Keyword(s):  
Dose Response ◽  
Elevated Serum ◽  
Peak Serum ◽  
Dose Response Relationship ◽  
Group Iii ◽  
Group I ◽  
Nitrous Oxide Anaesthesia ◽  
Oxide Anaesthesia ◽  
Healthy Adult Male ◽  
Dose Response Study

The metabolism of enflurane, used as a supplement to muscle relaxant and nitrous oxide anaesthesia, was studied in 19 healthy adult male surgical patients; seven control patients received halothane. Patients receiving enflurane were randomly allocated to three groups: Group I—1/2 MAC for 1/2 hour (dosage=1/4 MAC hour) Group II—1/2 MAC for 2 hours (dosage=1 MAC hour) Group III—1/2 MAC for 4 hours (dosage=2 MAC hours) Metabolism of enflurane to inorganic fluoride (F-) was indicated by elevated serum F-concentration and elevated urinary excretion of F-. Peak serum F- concentration was measured in samples collected immediately at the end of enflurane anaesthesia and fell thereafter, approaching pre-operative levels at 48 hours; mean peak serum F- was 23·6± 4·2 μmol/l after 2 MAC hours of enflurane, 17·7±2·8 μmol/l after 1 MAC hour and 10·5± 0·9 μmol/l after 1/4 MAC hour. Nephrotoxic levels of serum F- (50 μmol/l) were not reached in any patient. Post anaesthetic renal function, including response to vasopressin, was normal in all groups. A dose-response relationship between enflurane dose and F- in serum and urine was established.

scholarly journals Cadmium levels in human breast tissue and estradiol serum levels: Is there a connection?

2021 ◽  
Vol 71 (6) ◽  
pp. 581-595
Author(s):  
Aleksandra Buha-Đorđević ◽  
Milena Anđelković ◽  
Elena Kačavenda ◽  
Dragana Javorac ◽  
Evica Antonijević-Miljaković ◽  
...  
Keyword(s):  
Dose Response ◽  
Breast Tissue ◽  
Environmental Pollutants ◽  
Serum Levels ◽  
Response Analysis ◽  
Data Sets ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Human Data ◽  
Malignant Breast

Cadmium (Cd), one of the most abundant environmental pollutants, is considered to have endocrine disrupting properties. However, data on the dose-response relationship between Cd dose and levels of hormones have been insufficiently studied, especially in human data sets. Thus, the aim of this study was to determine the possibility of analyzing data obtained from a case-control study in female patients with benign/malignant breast tumors, using the Benchmark dose (BMD) concept. The collected data on Cd levels in breast tissue and estrogen serum levels were processed in PROAST software using different variables. The dose-response relationship between the internal dose of Cd and estradiol levels in the serum was investigated and BMD intervals were calculated. The dose-response relationship between the Cd concentration in breast tissue and the estradiol serum level was shown, indicating lower estradiol serum levels as a consequence of higher Cd concentrations in breast tissue. As one of the few studies analyzing human data using the BMD approach, these findings could have a pivotal role in dose response analysis of data collected from human studies.

A SUBCUTANEOUS INJECTION ASSAY FOR ANTI-ANDROGENS IN THE CHICK

1962 ◽  
Vol 41 (2) ◽  
pp. 268-273 ◽  
Author(s):  
Ralph I. Dorfman
Keyword(s):  
Dose Response ◽  
Subcutaneous Injection ◽  
Response Relationship ◽  
Dose Response Relationship

ABSTRACT The stimulating action of testosterone on the chick's comb can be inhibited by the subcutaneous injection of 0.1 mg of norethisterone or Ro 2-7239 (2-acetyl-7-oxo-1,2,3,4,4a,4b,5,6,7,9,10,10a-dodecahydrophenanthrene), 0.5 mg of cortisol or progesterone, and by 4.5 mg of Mer-25 (1-(p-2-diethylaminoethoxyphenyl)-1-phenyl-2-p-methoxyphenyl ethanol). No dose response relationship could be established. Norethisterone was the most active anti-androgen by this test.

Mathematical Interpretation of the Pharmacodynamics of Homoeopathic Medicines

2021 ◽  
Vol 34 (01) ◽  
pp. 003-016
Author(s):  
John Michel Warner
Keyword(s):  
Immune System ◽  
Immune Responses ◽  
Dose Response ◽  
Oral Route ◽  
Response Relationship ◽  
Dose Response Relationship ◽  
Force Line ◽  
Administration Routes ◽  
Medicinal Substances ◽  
Medicine Administration

AbstractAccording to Hahnemann, homoeopathic medicines must be great immune responses inducers. In crude states, these medicines pose severe threats to the immune system. So, the immune-system of an organism backfires against the molecules of the medicinal substances. The complex immune response mechanism activated by the medicinal molecules can handle any threats which are similar to the threats posed by the medicinal molecules. The intersectional operation of the two sets, medicine-induced immune responses and immune responses necessary to cure diseases, shows that any effective homoeopathic medicine, which is effective against any disease, can induce immune responses which are necessary to cure the specific disease. In this article, this mechanism has been exemplified by the action of Silicea in human body. Also, a neuroimmunological assessment of the route of medicine administration shows that the oral cavity and the nasal cavity are two administration-routes where the smallest doses (sometimes even few molecules) of a particular homoeopathic medicine induce the most effective and sufficient (in amount) purgatory immune responses. Administering the smallest unitary doses of Silicea in the oral route can make significant changes in the vital force line on the dose–response relationship graph. The dose–response relationship graph further implicates that the most effective dose of a medicine must be below the lethality threshold. If multiple doses of any medicine are administered at same intervals, the immune-system primarily engages with the medicinal molecules; but along the passage of time, the engagement line splits into two: one engages with the medicinal molecules and another engages with diseases. The immune system's engagement with the diseases increases along the passage of time, though the engagement with the medicinal molecules gradually falls with the administration of descending doses. Necessarily, I have shown through mathematical logic that the descending doses, though they seem to be funny, can effectively induce the most effective immune responses.

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