A dog (5.6 kg, 4-year-old, castrated male, Miniature pinscher) with diffuse symmetric alopecia on the chest and excessive scales was referred to Veterinary Medical Teaching Hospital of Chungnam National University, Korea. On physical examination, diffuse alopecia on ventral aspect of the neck and caudomedial thighs, and severe scales were presented. Dermatologic tests of lesions revealed bacterial infections. Histopathologically, atrophy of hair bulb was observed in the severely alopecic lesion of caudomedial thighs. ACTH stimulation test was performed to differentiate the endocrine disorder related to generalized alopecia. The pre-ACTH serum testosterone and progesterone concentrations were above normal ranges and the post-ACTH serum testosterone concentration was high. The pre- and post-ACTH serum estradiol and cortisol concentrations were within normal ranges. Canine pattern alopecia was diagnosed based on history, physical examination, hormonal assay and dermatohistopathologic examination. After 3 months of melatonin administration, multifocal alopecia on the trunk was improved and general hair regrowth was identified.

Melatonin, the principal hormone of the vertebral pineal gland, participates in the regulation of cardiovascular system in vitro and in vivo. However, the effects of melatonin on vascular tissues are still vague. The aim of this study was to assess the relationship between phospholipase C (PLC) and nitric oxide synthase (NOS)/cyclic guanosine 3',5'-monophosphate (cGMP) signaling cascade in the relaxatory action of melatonin in isolated rat aorta. Melatonin induced a concentration-dependent relaxation in phenylephrine (PE)- and KCl-precontraceted endothelium intact (+E) aortic rings.

Melatonin, the principal hormone of the vertebral pineal gland, participates in the regulation of cardiovascular system in vitro and in vivo. Lithium inhibits both inositol polyphosphate phosphatase (IPPase) and inositol monophosphatase (IMPase), which are involved in a wide range of signal transduction pathways. The aim of the present study was to assess the effect of lithium on endothelial-dependent relaxation to melatonin and on the melatonin-induced inhibition of contraction by phenylephrine (PE) in isolated rat aorta. Melatonin induced a concentration-dependent relaxation in PE-precontracted in endothelium-intact (+E) aortic rings.

The effects of melatonin and Light treatments on the reproductive performance of yearling Suffolk rams were investigated. The two groups (A, n = 8; B, n = 8) were given a priming period of long days (18 h Light (L): 6 h dark (D) during 1st February to 14th March. During 14th March to 9th September, group A was exposed to local light + melatonin Implants (Regulin) at 5 weekly intervals, group B was exposed to local light + melatonin Fed (M- 5250) alongwith the feed. The group (C, n = 8) in the local light during 1st February to 14th March and during 14th March to 9th September remained on local light + melatonin implants (Regulin) at 5-weekly intervals. However, the group (D, n=8) was treated as control and kept on local light environment (Lat. 51 degree 43'N) throughout the experiment. Testis diameter, sexual behaviours and semen quality were used to assess reproductive performances. The treatment to group A & B resulted in a significant advancement in high reproductive performance. The treatment to group C indicated that the abrupt application of melatonin in mid March resulted in a weak response in terms of all the criteria of assessment. The investigation indicated that seasonal fluctuations in reproductive behaviour and semen quality may be rephrased by the application of light and melatonin treatments and that these treatments may be considered for the preparation of rams for out of season breeding.