. 2022 Dec 1;13:1061317. doi: 10.3389/fendo.2022.1061317

Table 3.

Results on the presence of components of the serotonin system in human primary cell cultures (PCC) or single cells (SC).

	Gestational period	Cell type	PCC/SC	mRNA	Protein	Activity	Study
Enzymes
TPH1	First trimester	Syncytiotrophoblast	PCC	+ ^a	n.a.	n.a.	(83)
	First trimester	Cytotrophoblasts	PCC	+ ^a	n.a.	n.a.	(83)
	First trimester	Extravillous cytotrophoblasts	PCC	+ ^a	n.a.	n.a.	(83)
	Term	Syncytiotrophoblast	PCC	+ ^a	+ ^e	n.a.	(83)
	Term	Cytotrophoblasts	PCC	+ ^a	+ ^e	n.a.	(83)
	Term	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Trophoblasts	PCC	n.a.	n.a.	+ ^g	(68)
TPH2	First trimester	Syncytiotrophoblast	PCC	+ ^a	n.a.	n.a.	(83)
	First trimester	Cytotrophoblasts	PCC	+ ^a	n.a.	n.a.	(83)
	First trimester	Extravillous cytotrophoblasts	PCC	+ ^a	n.a.	n.a.	(83)
	Term	Syncytiotrophoblast	PCC	+ ^a	+ ^e	n.a.	(83)
	Term	Cytotrophoblasts	PCC	+ ^a	+ ^e	n.a.	(83)
	Term	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	(+) ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
MAOA	First trimester	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(88)
	First trimester	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)
	Term	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(87)
	Term	Trophoblasts	PCC	+ ^a	n.a.	n.a.	(89)
	Term	Feto-placental endothelial cells	PCC	+ ^a	n.a.	n.a.	(89)
MAOB	First trimester	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(88)
	First trimester	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	Term	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
Transporters
SERT	First trimester	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(88)
(SLC6A4)	First trimester	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	(+) ^b	n.a.	n.a.	(88)
	Term	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(87)
	Term	Syncytiotrophoblast	PCC	+ ^c	+ ^e	n.a.	(80)
	Term	Cytotrophoblasts	PCC	+ ^c	+ ^e	n.a.	(80)
	Term	Feto-placental endothelial cells	PCC	(+) ^a	n.a.	−	(89)
OCT1	Term	Trophoblasts	PCC	(+) ^a	n.a.	n.a.	(89)
(SLC22A1)	Term	Feto-placental endothelial cells	PCC	(+)/− ^a	n.a.	n.a.	(89)
OCT2	Term	Trophoblasts	PCC	− ^a	n.a.	n.a.	(89)
(SLC22A2)	Term	Feto-placental endothelial cells	PCC	− ^a	n.a.	n.a.	(89)
OCT3	First trimester	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(88)
(SLC22A3)	First trimester	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)
	Term	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Trophoblasts	PCC	(+)/− ^a	n.a.	n.a.	(89)
	Term	Feto-placental endothelial cells	PCC	(+)/− ^a	n.a.	n.a.	(89)
PMAT	First trimester	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(88)
(SLC29A4)	First trimester	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	Term	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Trophoblasts	PCC	− ^a	n.a.	−	(89)
	Term	Feto-placental endothelial cells	PCC	+ ^a	n.a.	+	(89)
VMAT1	First trimester	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(88)
(SLC18A1)	First trimester	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	Term	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
VMAT2	Term	Trophoblasts	PCC	− ^d	n.a.	−	(90)
(SLC18A2)	Term	Syncytiotrophoblast	SC	(+) ^b	n.a.	n.a.	(87)
	Term	Cytotrophoblasts	SC	(+) ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(87)
Receptors
HTR2A	Term	Cytrophoblasts	PCC	+ ^c	+ ^e	n.a.	(80)
	Term	Syncytiotrophoblast	PCC	+ ^c	+ ^e	n.a.	(80)
	Term	Cytotrophoblasts	SC	(+) ^b	n.a.	n.a.	(87)
	Term	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
	Term	Trophoblasts	PCC	n.a.	+ ^f	n.a.	(91)
HTR2B	First trimester	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)
	First trimester	Syncytiotrophoblast	SC	− ^b	n.a.	n.a.	(88)
	First trimester	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(88)
	Term	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(87)
	Term	Syncytiotrophoblast	SC	+ ^b	n.a.	n.a.	(87)
	Term	Extravillous cytotrophoblasts	SC	− ^b	n.a.	n.a.	(87)
HTR1D	Term	Syncytotrophoblast	SC	(+) ^b	n.a.	n.a.	(87)
HTR1F	Term	Syncytotrophoblast	SC	(+) ^b	n.a.	n.a.	(87)
HTR3 (A)	Term	Cytotrophoblasts	SC	(+) ^b	n.a.	n.a.	(87)
HTR4	Term	Cytotrophoblasts	SC	(+) ^b	n.a.	n.a.	(87)
HTR7	First trimester	Cytotrophoblasts	SC	+ ^b	n.a.	n.a.	(88)

RT−qPCR (quantitative reverse transcriptase−polymerase chain reaction.

RNA-sequencing.

RT−PCR (reverse transcription−end point PCR).

Northern blot.

Western blot.

Receptor binding studies.

The activity assay used does not distinguish between the activity of TPH1 and TPH2.

n.a.: not analysed; +: detected; −: not detected; (+): low levels detected; (+)/−: low levels detected or below detection limit.