. 2001 Mar 1;21(5):1532–1537. doi: 10.1523/JNEUROSCI.21-05-01532.2001

Table 1.

Developmental changes in synaptic plasticity and 5-HT content in the rat visual cortex

Age (weeks)	White matter-II/III pathway		Layer IV–II/III pathway		5-HT content (pg/μg protein)
Age (weeks)	Maximal synaptic potential (mV)	LTP (%)	Maximal synaptic potential (mV)	LTP (%)	5-HT content (pg/μg protein)
2	0.58 ± 0.09	139.4 ± 6.9	0.94 ± 0.05	140.5 ± 5.7	n.d.
3	0.54 ± 0.05	137.0 ± 7.4	0.93 ± 0.10	139.2 ± 4.2	86.5 ± 13.8
4	0.62 ± 0.11	121.1 ± 6.7	0.94 ± 0.10	141.5 ± 8.2	155.5 ± 18.4
5	0.60 ± 0.04	102.5 ± 7.3**	0.89 ± 0.05	138.9 ± 7.2	309.9 ± 30.6**

Field potentials were recorded in the white matter-layer II/III pathway or in the layer IV–layer II/III pathway of the visual cortex slices obtained from 2- to 5-week-old rats. The size of maximal synaptic potential was determined by constructing the input–output curve before tetanic stimulation. The average percentage amplitude of synaptic potentials 30–60 min after tetanic stimulation was calculated as an index of LTP. n.d., Not determined. Data are represented as the means ± SEM. (n = 5 for electrophysiology,n = 12 for determination of 5-HT). **p< 0.01 versus 3 weeks; Tukey's test after ANOVA.