Age-dependent changes in 24-hour rhythms of catecholamine content and turnover in hypothalamus, corpus striatum and pituitary gland of rats injected with Freund's adjuvant

Table 3 Cosinor analysis on 24-h changes in hypophysial NE and DA content, in young and old rats injected with Freund's adjuvant or its vehicle 18 days earlier.

	Mesor	Amplitude	Acrophase (h, min)	Percent of rhythm
NE CONTENT
Neurointermediate lobe
Young, Freund's adjuvant	208 ± 32	117	03:34 ± 01:09	40 ± 7.1
Young, adjuvant's vehicle	216 ± 26	102 ± 14	02:31 ± 02:02	51 ± 6.5
Old, Freund's adjuvant	125 ± 15^*	n.s.	n.s.	n.s.
Old, adjuvant's vehicle	149 ± 19^*	69 ± 8^*	02:34 ± 00:56	37 ± 4.4
DA CONTENT
Neurointermediate lobe
Young, Freund's adjuvant	277 ± 43	125 ± 23	04:23 ± 02:00	30 ± 6.2
Young, adjuvant's vehicle	250 ± 40	171± 48	02:47 ± 01:54	86 ± 12
Old, Freund's adjuvant	174 ± 20^*	n.s.	n.s.	n.s.
Old, adjuvant's vehicle	112 ± 42^*	49 ± 22^*	03:25 ± 01:54	61 ± 11
Anterior hypophysis
Young, Freund's adjuvant	20 ± 3	-	-	-
Young, adjuvant's vehicle	21± 4	11± 3	10:31 ± 01:05	75 ± 11
Old, Freund's adjuvant	30 ± 6^*	n.s.	n.s.	n.s.
Old, adjuvant's vehicle	39 ± 7^*	-	-	-

Shown are the means ± S.E.M. (n = 5–7/group). Mesor and amplitude values are expressed as pg/mg. Percent of rhythm defines the part of variation that could be explained by a cosine function in Cosinor. Asterisks designate significant differences (p < 0.05) as compared to the respective young counterparts in a one-tailed Student's t test. n.s.: not significant daily changes in a one-way ANOVA; (-): not significant changes in Cosinor

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