( There ( ( may ( ( ( be ( ( ( as ( many ( as four ) ) ) types ) ( of ( CGRP receptors ) ) ) ) , ) ( as well ) ) ) . ) )
(ROOT (S (NP (EX There)) (VP (MD may) (VP (VB be) (NP (NP (QP (RB as) (JJ many) (IN as) (CD four)) (NNS types)) (PP (IN of) (NP (NNP CGRP) (NNS receptors)))) (, ,) (ADVP (RB as) (RB well)))) (. .)))
There may be as many as four types of CGRP receptors, as well.
(ROOT (S (NP (EX There)) (VP (VBP are) (NP (NP (CD four) (NNS types)) (PP (IN of) (NP (NNS bosons))))) (. .)))