The sequence of structural changes in goat hair follicles was investigated using melatonin implants to advance and synchronize spring hair growth. Ten pasture fed cashmere wethers each received a controlled release formulation of 70 mg of melatonin on September 1 1989, and showed plasma melatonin elevated above physiological levels over 14 days post-treatment (914 +/- 154 pg/ml [mean +/- SEM] on day 14). In ten untreated animals, daytime plasma melatonin was 19.9 +/- 4.7 pg/ml. Histological examination of skin biopsies taken over the 14 days from the start of the experiment showed that primary hair follicles of goats with manipulated hormone levels had initiated fiber growth (entered proanagen), whereas primary follicles of untreated goats largely remained in the quiescent phase (telogen). A standardized terminology was used to describe the sequence of events during induced proanagen. Structural reorganization of follicles began in treated animals between days 6 and 12 post-treatment, and emergent fibers grew by day 24. Advancement of spring fiber growth was associated with a suppression of the normal rise in plasma prolactin concentration. Prolactin levels in untreated goats increased from 7.4 +/- 1.8 ng/ml on day 1 to 12.8 +/- 1.6 ng/ml on day 14, but declined in treated goats from 6.3 +/- 2.3 ng/ml to 2.2 +/- 0.8 ng/ml over the same period.
Background: The Health Research Council of New Zealand is the first major government funding agency to use a lottery to allocate research funding for their Explorer Grant scheme. This is a somewhat controversial approach because, despite the documented problems of peer review, many researchers believe that funding should be allocated solely using peer review, and peer review is used almost ubiquitously by funding agencies around the world. Given the rarity of alternative funding schemes, there is interest in hearing from the first cohort of researchers to ever experience a lottery. Additionally, the Health Research Council of New Zealand wanted to hear from applicants about the acceptability of the randomisation process and anonymity of applicants. Methods: This paper presents the results of a survey of Health Research Council applicants from 2013 to 2019. The survey asked about the acceptability of using a lottery and if the lottery meant researchers took a different approach to their application. Results: The overall response rate was 39% (126 of 325 invites), with 30% (76 of 251) from applicants in the years 2013 to 2018, and 68% (50 of 74) for those in the year 2019 who were not aware of the funding result. There was agreement that randomisation is an acceptable method for allocating Explorer Grant funds with 63% (n = 79) in favour and 25% (n = 32) against. There was less support for allocating funds randomly for other grant types with only 40% (n = 50) in favour and 37% (n = 46) against. Support for a lottery was higher amongst those that had won funding. Multiple respondents stated that they supported a lottery when ineligible applications had been excluded and outstanding applications funded, so that the remaining applications were truly equal. Most applicants reported that the lottery did not change the time they spent preparing their application. Conclusions: The Health Research Council's experience through the Explorer Grant scheme supports further uptake of a modified lottery.
Frequent blood samples were removed from a utero-ovarian vein, a jugular vein and a femoral artery of 5 ewes during luteolysis. Analysis of these samples for oxytocin-associated neurophysin revealed a significant venous-arterial difference across the ovary and uterus but not across the head. This occurred during the pulsatile surges as well as when levels were basal and confirms the corpus luteum as a major source of the pulsatile surges of oxytocin-associated neurophysin and oxytocin that occur during CL regression and also of the elevated luteal phase concentrations of both hormones. The pulsatile surges of oxytocin-associated neurophysin measured in the utero-ovarian vein were accompanied by the release of an approximately equimolar amount of oxytocin. The concentration of PGF-2 alpha in the utero-ovarian vein samples began to increase before the levels of oxytocin and oxytocin-associated neurophysin started to increase. This suggests that uterine PGF-2 alpha initiates the release of ovarian oxytocin and oxytocin-associated neurophysin during luteolysis in the ewe.
Although prolactin (PRL) receptors are found in many mammalian tissues, specific PRL binding to mammalian skin has not been demonstrated. In view of the temporal relationships observed between photoperiod, circulating PRL and pelage replacement in seasonally responsive mammals, we sought to provide evidence of PRL receptors in ovine skin. Cryosections of skin from New Zealand Wiltshire ewes were incubated with radiolabelled human GH (125I-hGH) and ovine PRL (125I-oPRL) in the presence and absence of excess unlabelled hormones (hGH, oPRL or ovine GH (oGH)). Binding was inhibited by unlabelled oPRL and hGH but not by oGH. In microautoradiographs, both radioligands were localised most strongly in the dermal papillae of wool follicles in the anagen (growth) phase of the hair cycle and in apocrine sweat glands. Higher levels of specific binding to dermal papilla cells, compared with the follicle epithelial matrix and the surrounding dermis, were confirmed by measurement of microautoradiograph silver grain density (respectively, 34.1 +/- 3.0, 11.4 +/- 1.0 and 5.5 +/- 0.5 grains per 100 microns2 (mean +/- S.E.M., n = 10)). Total binding for 125I-hGH and 125I-oPRL radioligands to follicle dermal papilla was not significantly different (34.1 +/- 3.0 vs 43.6 +/- 2.5 grains per 100 microns2, n = 10) but the level of non-specific binding of 123I-oPRL was higher than for 125I-hGH (18.9 +/- 1.4 vs 6.1 +/- 0.6 grains per 100 microns2, n = 10; P < 0.001). Binding assays of receptors in crude microsomal membranes extracted from ovine skin were used to ascertain binding capacity and specificity.(ABSTRACT TRUNCATED AT 250 WORDS)
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