I recall that some on this board have commented about their blood pressure being higher when they rise in the morning, then the BP decreases after they have been up an hour or so. Apparently some people are dippers (those whose BP decreases considerably at night) and others are non-dippers (those whose BP increases during the night).
Check out this abstract: [url]http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_u ids=12699131&dopt=Abstract[/url]
Here is a quote from it:
CONCLUSIONS: NDIP hypertensive patients differ from DIP hypertensives by having an impaired nocturnal melatonin secretion. Thus, melatonin may play a role in the circadian rhythm of blood pressure in hypertensive patients.
I also read a research article lately that elevated homocysteine is some times related to melatonin. Amazing how all these things can be so intertwined!