Q:

Which human body hormonal systems exhibit 24 hour diurnal cyclical activity?

I'm researching the possible connection between the dream content and the activity of various organ or hormonal systems within the human body. I'm looking for information on biological cycles within the human body that occur on a 24 hour cycle and may influence the sleep cycle, dream content or the overall state of awareness.
So far I was able to find:
Adrenaline, cortisol, testesterone - circadian endogenous cycle. 
leptin, glucose, insuline  -  peak with awakening, decline with bedtime
What else within the human body is functioning on a predictable 24 hour cycle?
Thank you for any information!

A:

The real answer is probably more than you want, but its easy to do better than the list above.  
I took a look through GEO for human circadian expression data and surprisingly I only found 2.
Looking at GSE2703 - the rhesus circadian expression experiment, they have shown 355 genes that are rhythmically expressed.  This is not a great experiment because they only looked over a single 24 hour period.  Its only the adrenal gland.  Nonetheless they found 355 genes which seemed to be circadian.  the table is supplemental data to the article,  listed below. 
I see a fibroblast growth factor receptor, some hydrocarbon nuclear receptor components, sterol regulatory factors, bone morphogenic protein 2, glutamate receptor, thrombonspondin receptor, ryanodine receptor 3 (what is that?) , lysophosphatidic acid G-protein-coupled receptor 2, purinergic receptor P2Y, G-protein coupled.  You might find more if you know what you are looking for. 
The other circadian study was on human muscle, which will no doubt give different answers.  I imagine circadian behavior is highly tissue dependent. 
Reference: Lemos DR, Downs JL, Urbanski HF. Twenty-four-hour rhythmic gene expression in the rhesus macaque adrenal gland. Mol Endocrinol 2006 May;20(5):1164-76

