Table 7.

Serotonergic-Mediated Calcium-Dependent Pharmaco-Mechanical Coupling Contractile Mechanisms with Development

Physiologic Variable	Fetus	Newborn	Adult	Reference
Amine to K+ Response Ratio (10−5 5-HT, 1.22×10−1 K)*	103±10 (343)	50±6 (167)	30±4	[17]
Amine to K+ Response Ratio (10−5 5-HT, 1.22×10−1 K)*	90±10 (129)	75±8 (107)	70±8	[17]
Amine-Induced Tension (g) (10−5 M 5-HT and 2×10−5 M Histamine)	2.0±0.2 (91)		2.2±0.2	[245]
Amine/K+max (%)	85±5a (224)		38±5	[245]
5-HT · K−1 induced tension†	2.0±0.3 (133)		1.5±0.2	[346]
5-HT · K−1 induced Δ [Ca2+]i†	40±5 (53)		75±7	[346]
5-HT · K−1 tension · [ΔCa2+]i†	0.05 (250)		0.02	[346]
pD2 for 5-HT-induced contr†‡	6.7±0.1		6.3±0.1	[47]
Maximum 45Ca uptake in response to 10−5 M 5-HT (μM · g dry wt−1 · min−1)	201±15 (156)		129±23	[348]
Maximal response to 5-HT	-		To 82% from 59%	[376]
pD2 for 5-HT response with BK channel blockade‡	To 7.51 from 7.05		To 7.75 from 7.15	[376]
Enhance 5-HT response with BK channel blockade (also %)	NSC		To 82 from 59	[376]
pD2 for 5-HT response with Kv channel blockade	-		To 7.49 from 7.15	[376]
Enhance 5-HT response with Kv channel blockade (also %)	To 85 from 67 (100)		To 79 from 59	[376]
pD2 for 5-HT response with KATP channel blockade‡	To 6.71 from 7.02		NSC	[376]
pD2 for 5-HT response with ERK1/2 inhibition‡	10-fold		2-fold	[19]
Emax with ERK1/2 inhibition (% decrease)	~37		~17	[19]

Values are mean ± SE of 5 or more in each group;

Values in parentheses represent % of adult value;

Significantly different from adult value:

^aP<0.001;

^†Basilar artery;

^‡Because these are logarithmic functions, percent change is not an accurate or appropriate representation;

^*CCA;

NSC – No Significant Change