The LH RH agonist Buserelin was continuously administered through the nose over an extended period to 5 patients with endometriosis at daily doses ranging between 300 micrograms and 1,200 micrograms. The clinical findings and endocrinological dynamics, with emphasis on PRL secretion function, were investigated and the findings below were obtained. The clinical findings showed Buserelin to be effective against endometriosis. The administration of Buserelin markedly inhibited the secretion of LH and FSH under LH-RH loading. The administration of Buserelin markedly inhibited the secretion of PRL and the degree of inhibition appeared to be dependent on the dose and duration of Buserelin administration. No correlation between E2 and PRL was observed during Buserelin administration. The findings suggest that Buserelin inhibits PRL secretion by direct CNS activity, not indirectly through inhibition of E2 production.

Control of blood retinol levels in cattle during fattening is important in the production of marbled beef. However, it is difficult to easily measure the blood retinol concentration in the field. In this study, we attempted to develop an analysis method that does not require blood cell separation and uses a compact fluorescence analyzer that can be carried around as a preliminary system for measuring blood retinol concentration in the field. This system was used to monitor blood retinol levels in 12 fattening cattle (14 to 27 months old) and demonstrated a strong correlation (r = 0.78) with the results obtained by the standard high‐performance liquid chromatography (HPLC) method. Stronger correlations (r = 0.87) were obtained until the cattle were 24 months of age. These results suggest that higher correlations can be expected to be obtained by improving the robustness of the extraction system. Refinements for practical use need to be considered, but whole blood extraction and the vitamin A analyzer that was developed show potential to be used for on‐farm monitoring of retinol levels.